diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index c597df7528..d60f6cd9de 100644
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -444,7 +444,7 @@ static int module_foreach(int argc, const char **argv, const char *prefix)
 	};
 
 	const char *const git_submodule_helper_usage[] = {
-		N_("git submodule--helper foreach [--quiet] [--recursive] [--] <command>"),
+		N_("git submodule foreach [--quiet] [--recursive] [--] <command>"),
 		NULL
 	};
 
@@ -582,7 +582,7 @@ static int module_init(int argc, const char **argv, const char *prefix)
 	};
 
 	const char *const git_submodule_helper_usage[] = {
-		N_("git submodule--helper init [<options>] [<path>]"),
+		N_("git submodule init [<options>] [<path>]"),
 		NULL
 	};
 
@@ -1185,7 +1185,7 @@ static int module_summary(int argc, const char **argv, const char *prefix)
 	};
 
 	const char *const git_submodule_helper_usage[] = {
-		N_("git submodule--helper summary [<options>] [<commit>] [--] [<path>]"),
+		N_("git submodule summary [<options>] [<commit>] [--] [<path>]"),
 		NULL
 	};
 
@@ -1349,7 +1349,7 @@ static int module_sync(int argc, const char **argv, const char *prefix)
 	};
 
 	const char *const git_submodule_helper_usage[] = {
-		N_("git submodule--helper sync [--quiet] [--recursive] [<path>]"),
+		N_("git submodule sync [--quiet] [--recursive] [<path>]"),
 		NULL
 	};
 
@@ -1818,7 +1818,7 @@ static int module_clone(int argc, const char **argv, const char *prefix)
 static void determine_submodule_update_strategy(struct repository *r,
 						int just_cloned,
 						const char *path,
-						const char *update,
+						enum submodule_update_type update,
 						struct submodule_update_strategy *out)
 {
 	const struct submodule *sub = submodule_from_path(r, null_oid(), path);
@@ -1828,9 +1828,7 @@ static void determine_submodule_update_strategy(struct repository *r,
 	key = xstrfmt("submodule.%s.update", sub->name);
 
 	if (update) {
-		if (parse_submodule_update_strategy(update, out) < 0)
-			die(_("Invalid update mode '%s' for submodule path '%s'"),
-				update, path);
+		out->type = update;
 	} else if (!repo_config_get_string_tmp(r, key, &val)) {
 		if (parse_submodule_update_strategy(val, out) < 0)
 			die(_("Invalid update mode '%s' configured for submodule path '%s'"),
@@ -1882,7 +1880,7 @@ struct update_data {
 	const char *prefix;
 	const char *recursive_prefix;
 	const char *displaypath;
-	const char *update_default;
+	enum submodule_update_type update_default;
 	struct object_id suboid;
 	struct string_list references;
 	struct submodule_update_strategy update_strategy;
@@ -2405,8 +2403,27 @@ static void ensure_core_worktree(const char *path)
 	}
 }
 
+static const char *submodule_update_type_to_label(enum submodule_update_type type)
+{
+	switch (type) {
+	case SM_UPDATE_CHECKOUT:
+		return "checkout";
+	case SM_UPDATE_MERGE:
+		return "merge";
+	case SM_UPDATE_REBASE:
+		return "rebase";
+	case SM_UPDATE_UNSPECIFIED:
+	case SM_UPDATE_NONE:
+	case SM_UPDATE_COMMAND:
+		break;
+	}
+	BUG("unreachable with type %d", type);
+}
+
 static void update_data_to_args(struct update_data *update_data, struct strvec *args)
 {
+	enum submodule_update_type update_type = update_data->update_default;
+
 	strvec_pushl(args, "submodule--helper", "update", "--recursive", NULL);
 	strvec_pushf(args, "--jobs=%d", update_data->max_jobs);
 	if (update_data->recursive_prefix)
@@ -2430,8 +2447,10 @@ static void update_data_to_args(struct update_data *update_data, struct strvec *
 		strvec_push(args, "--require-init");
 	if (update_data->depth)
 		strvec_pushf(args, "--depth=%d", update_data->depth);
-	if (update_data->update_default)
-		strvec_pushl(args, "--update", update_data->update_default, NULL);
+	if (update_type != SM_UPDATE_UNSPECIFIED)
+		strvec_pushf(args, "--%s",
+			     submodule_update_type_to_label(update_type));
+
 	if (update_data->references.nr) {
 		struct string_list_item *item;
 		for_each_string_list_item(item, &update_data->references)
@@ -2601,9 +2620,15 @@ static int module_update(int argc, const char **argv, const char *prefix)
 			   N_("path"),
 			   N_("path into the working tree, across nested "
 			      "submodule boundaries")),
-		OPT_STRING(0, "update", &opt.update_default,
-			   N_("string"),
-			   N_("rebase, merge, checkout or none")),
+		OPT_SET_INT(0, "checkout", &opt.update_default,
+			N_("use the 'checkout' update strategy (default)"),
+			SM_UPDATE_CHECKOUT),
+		OPT_SET_INT('m', "merge", &opt.update_default,
+			N_("use the 'merge' update strategy"),
+			SM_UPDATE_MERGE),
+		OPT_SET_INT('r', "rebase", &opt.update_default,
+			N_("use the 'rebase' update strategy"),
+			SM_UPDATE_REBASE),
 		OPT_STRING_LIST(0, "reference", &opt.references, N_("repo"),
 			   N_("reference repository")),
 		OPT_BOOL(0, "dissociate", &opt.dissociate,
@@ -2619,7 +2644,7 @@ static int module_update(int argc, const char **argv, const char *prefix)
 		OPT_BOOL(0, "progress", &opt.progress,
 			    N_("force cloning progress")),
 		OPT_BOOL(0, "require-init", &opt.require_init,
-			   N_("disallow cloning into non-empty directory")),
+			   N_("disallow cloning into non-empty directory, implies --init")),
 		OPT_BOOL(0, "single-branch", &opt.single_branch,
 			 N_("clone only one branch, HEAD or --branch")),
 		OPT_PARSE_LIST_OBJECTS_FILTER(&filter_options),
@@ -2643,6 +2668,9 @@ static int module_update(int argc, const char **argv, const char *prefix)
 	argc = parse_options(argc, argv, prefix, module_update_options,
 			     git_submodule_helper_usage, 0);
 
+	if (opt.require_init)
+		opt.init = 1;
+
 	if (filter_options.choice && !opt.init) {
 		usage_with_options(git_submodule_helper_usage,
 				   module_update_options);
@@ -2651,9 +2679,7 @@ static int module_update(int argc, const char **argv, const char *prefix)
 	opt.filter_options = &filter_options;
 
 	if (opt.update_default)
-		if (parse_submodule_update_strategy(opt.update_default,
-						    &opt.update_strategy) < 0)
-			die(_("bad value for update parameter"));
+		opt.update_strategy.type = opt.update_default;
 
 	if (module_list_compute(argc, argv, prefix, &pathspec, &opt.list) < 0) {
 		list_objects_filter_release(&filter_options);
@@ -2785,7 +2811,7 @@ static int absorb_git_dirs(int argc, const char **argv, const char *prefix)
 	};
 
 	const char *const git_submodule_helper_usage[] = {
-		N_("git submodule--helper absorb-git-dirs [<options>] [<path>...]"),
+		N_("git submodule absorbgitdirs [<options>] [<path>...]"),
 		NULL
 	};
 
@@ -2890,7 +2916,7 @@ static int module_set_url(int argc, const char **argv, const char *prefix)
 		OPT_END()
 	};
 	const char *const usage[] = {
-		N_("git submodule--helper set-url [--quiet] <path> <newurl>"),
+		N_("git submodule set-url [--quiet] <path> <newurl>"),
 		NULL
 	};
 
@@ -2929,8 +2955,8 @@ static int module_set_branch(int argc, const char **argv, const char *prefix)
 		OPT_END()
 	};
 	const char *const usage[] = {
-		N_("git submodule--helper set-branch [-q|--quiet] (-d|--default) <path>"),
-		N_("git submodule--helper set-branch [-q|--quiet] (-b|--branch) <branch> <path>"),
+		N_("git submodule set-branch [-q|--quiet] (-d|--default) <path>"),
+		N_("git submodule set-branch [-q|--quiet] (-b|--branch) <branch> <path>"),
 		NULL
 	};
 
@@ -3274,7 +3300,7 @@ static int module_add(int argc, const char **argv, const char *prefix)
 	};
 
 	const char *const usage[] = {
-		N_("git submodule--helper add [<options>] [--] <repository> [<path>]"),
+		N_("git submodule add [<options>] [--] <repository> [<path>]"),
 		NULL
 	};
 
@@ -3387,7 +3413,7 @@ static struct cmd_struct commands[] = {
 	{"deinit", module_deinit, 0},
 	{"summary", module_summary, SUPPORT_SUPER_PREFIX},
 	{"push-check", push_check, 0},
-	{"absorb-git-dirs", absorb_git_dirs, SUPPORT_SUPER_PREFIX},
+	{"absorbgitdirs", absorb_git_dirs, SUPPORT_SUPER_PREFIX},
 	{"is-active", is_active, 0},
 	{"check-name", check_name, 0},
 	{"config", module_config, 0},
diff --git a/contrib/subtree/git-subtree.sh b/contrib/subtree/git-subtree.sh
index 1af1d9653e..7562a395c2 100755
--- a/contrib/subtree/git-subtree.sh
+++ b/contrib/subtree/git-subtree.sh
@@ -50,6 +50,14 @@ m,message=    use the given message as the commit message for the merge commit
 
 indent=0
 
+# Usage: say [MSG...]
+say () {
+	if test -z "$arg_quiet"
+	then
+		printf '%s\n' "$*"
+	fi
+}
+
 # Usage: debug [MSG...]
 debug () {
 	if test -n "$arg_debug"
@@ -60,7 +68,7 @@ debug () {
 
 # Usage: progress [MSG...]
 progress () {
-	if test -z "$GIT_QUIET"
+	if test -z "$arg_quiet"
 	then
 		if test -z "$arg_debug"
 		then
@@ -146,6 +154,7 @@ main () {
 	eval "$set_args"
 
 	# Begin "real" flag parsing.
+	arg_quiet=
 	arg_debug=
 	arg_prefix=
 	arg_split_branch=
@@ -161,7 +170,7 @@ main () {
 
 		case "$opt" in
 		-q)
-			GIT_QUIET=1
+			arg_quiet=1
 			;;
 		-d)
 			arg_debug=1
@@ -252,7 +261,7 @@ main () {
 	dir="$(dirname "$arg_prefix/.")"
 
 	debug "command: {$arg_command}"
-	debug "quiet: {$GIT_QUIET}"
+	debug "quiet: {$arg_quiet}"
 	debug "dir: {$dir}"
 	debug "opts: {$*}"
 	debug
diff --git a/git-instaweb.sh b/git-instaweb.sh
index 4349566c89..c68f49454c 100755
--- a/git-instaweb.sh
+++ b/git-instaweb.sh
@@ -102,7 +102,7 @@ resolve_full_httpd () {
 
 start_httpd () {
 	if test -f "$fqgitdir/pid"; then
-		say "Instance already running. Restarting..."
+		echo "Instance already running. Restarting..."
 		stop_httpd
 	fi
 
diff --git a/git-sh-setup.sh b/git-sh-setup.sh
index d92df37e99..ce273fe0e4 100644
--- a/git-sh-setup.sh
+++ b/git-sh-setup.sh
@@ -57,15 +57,6 @@ die_with_status () {
 	exit "$status"
 }
 
-GIT_QUIET=
-
-say () {
-	if test -z "$GIT_QUIET"
-	then
-		printf '%s\n' "$*"
-	fi
-}
-
 if test -n "$OPTIONS_SPEC"; then
 	usage() {
 		"$0" -h
@@ -285,13 +276,6 @@ get_author_ident_from_commit () {
 	parse_ident_from_commit author AUTHOR
 }
 
-# Clear repo-local GIT_* environment variables. Useful when switching to
-# another repository (e.g. when entering a submodule). See also the env
-# list in git_connect()
-clear_local_git_env() {
-	unset $(git rev-parse --local-env-vars)
-}
-
 # Generate a virtual base file for a two-file merge. Uses git apply to
 # remove lines from $1 that are not in $2, leaving only common lines.
 create_virtual_base() {
diff --git a/git-submodule.sh b/git-submodule.sh
index fd0b4a2c94..5e5d21c010 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -30,6 +30,7 @@ GIT_PROTOCOL_FROM_USER=0
 export GIT_PROTOCOL_FROM_USER
 
 command=
+quiet=
 branch=
 force=
 reference=
@@ -40,8 +41,9 @@ require_init=
 files=
 remote=
 nofetch=
-update=
-prefix=
+rebase=
+merge=
+checkout=
 custom_name=
 depth=
 progress=
@@ -56,17 +58,6 @@ isnumber()
 	n=$(($1 + 0)) 2>/dev/null && test "$n" = "$1"
 }
 
-# Sanitize the local git environment for use within a submodule. We
-# can't simply use clear_local_git_env since we want to preserve some
-# of the settings from GIT_CONFIG_PARAMETERS.
-sanitize_submodule_env()
-{
-	save_config=$GIT_CONFIG_PARAMETERS
-	clear_local_git_env
-	GIT_CONFIG_PARAMETERS=$save_config
-	export GIT_CONFIG_PARAMETERS
-}
-
 #
 # Add a new submodule to the working tree, .gitmodules and the index
 #
@@ -90,7 +81,7 @@ cmd_add()
 			force=$1
 			;;
 		-q|--quiet)
-			GIT_QUIET=1
+			quiet=1
 			;;
 		--progress)
 			progress=1
@@ -138,7 +129,7 @@ cmd_add()
 		usage
 	fi
 
-	git ${wt_prefix:+-C "$wt_prefix"} ${prefix:+--super-prefix "$prefix"} submodule--helper add ${GIT_QUIET:+--quiet} ${force:+--force} ${progress:+"--progress"} ${branch:+--branch "$branch"} ${reference_path:+--reference "$reference_path"} ${dissociate:+--dissociate} ${custom_name:+--name "$custom_name"} ${depth:+"$depth"} -- "$@"
+	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper add ${quiet:+--quiet} ${force:+--force} ${progress:+"--progress"} ${branch:+--branch "$branch"} ${reference_path:+--reference "$reference_path"} ${dissociate:+--dissociate} ${custom_name:+--name "$custom_name"} ${depth:+"$depth"} -- "$@"
 }
 
 #
@@ -154,7 +145,7 @@ cmd_foreach()
 	do
 		case "$1" in
 		-q|--quiet)
-			GIT_QUIET=1
+			quiet=1
 			;;
 		--recursive)
 			recursive=1
@@ -169,7 +160,7 @@ cmd_foreach()
 		shift
 	done
 
-	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper foreach ${GIT_QUIET:+--quiet} ${recursive:+--recursive} -- "$@"
+	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper foreach ${quiet:+--quiet} ${recursive:+--recursive} -- "$@"
 }
 
 #
@@ -184,7 +175,7 @@ cmd_init()
 	do
 		case "$1" in
 		-q|--quiet)
-			GIT_QUIET=1
+			quiet=1
 			;;
 		--)
 			shift
@@ -200,7 +191,7 @@ cmd_init()
 		shift
 	done
 
-	git ${wt_prefix:+-C "$wt_prefix"} ${prefix:+--super-prefix "$prefix"} submodule--helper init ${GIT_QUIET:+--quiet} -- "$@"
+	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper init ${quiet:+--quiet} -- "$@"
 }
 
 #
@@ -217,7 +208,7 @@ cmd_deinit()
 			force=$1
 			;;
 		-q|--quiet)
-			GIT_QUIET=1
+			quiet=1
 			;;
 		--all)
 			deinit_all=t
@@ -236,7 +227,7 @@ cmd_deinit()
 		shift
 	done
 
-	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper deinit ${GIT_QUIET:+--quiet} ${force:+--force} ${deinit_all:+--all} -- "$@"
+	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper deinit ${quiet:+--quiet} ${force:+--force} ${deinit_all:+--all} -- "$@"
 }
 
 #
@@ -251,10 +242,7 @@ cmd_update()
 	do
 		case "$1" in
 		-q|--quiet)
-			GIT_QUIET=1
-			;;
-		-v)
-			unset GIT_QUIET
+			quiet=1
 			;;
 		--progress)
 			progress=1
@@ -263,7 +251,6 @@ cmd_update()
 			init=1
 			;;
 		--require-init)
-			init=1
 			require_init=1
 			;;
 		--remote)
@@ -276,7 +263,7 @@ cmd_update()
 			force=$1
 			;;
 		-r|--rebase)
-			update="rebase"
+			rebase=1
 			;;
 		--reference)
 			case "$2" in '') usage ;; esac
@@ -290,13 +277,13 @@ cmd_update()
 			dissociate=1
 			;;
 		-m|--merge)
-			update="merge"
+			merge=1
 			;;
 		--recursive)
 			recursive=1
 			;;
 		--checkout)
-			update="checkout"
+			checkout=1
 			;;
 		--recommend-shallow)
 			recommend_shallow="--recommend-shallow"
@@ -349,7 +336,7 @@ cmd_update()
 	done
 
 	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper update \
-		${GIT_QUIET:+--quiet} \
+		${quiet:+--quiet} \
 		${force:+--force} \
 		${progress:+"--progress"} \
 		${remote:+--remote} \
@@ -357,8 +344,9 @@ cmd_update()
 		${init:+--init} \
 		${nofetch:+--no-fetch} \
 		${wt_prefix:+--prefix "$wt_prefix"} \
-		${prefix:+--recursive-prefix "$prefix"} \
-		${update:+--update "$update"} \
+		${rebase:+--rebase} \
+		${merge:+--merge} \
+		${checkout:+--checkout} \
 		${reference:+"$reference"} \
 		${dissociate:+"--dissociate"} \
 		${depth:+"$depth"} \
@@ -409,7 +397,7 @@ cmd_set_branch() {
 		shift
 	done
 
-	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper set-branch ${GIT_QUIET:+--quiet} ${branch:+--branch "$branch"} ${default:+--default} -- "$@"
+	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper set-branch ${quiet:+--quiet} ${branch:+--branch "$branch"} ${default:+--default} -- "$@"
 }
 
 #
@@ -422,7 +410,7 @@ cmd_set_url() {
 	do
 		case "$1" in
 		-q|--quiet)
-			GIT_QUIET=1
+			quiet=1
 			;;
 		--)
 			shift
@@ -438,7 +426,7 @@ cmd_set_url() {
 		shift
 	done
 
-	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper set-url ${GIT_QUIET:+--quiet} -- "$@"
+	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper set-url ${quiet:+--quiet} -- "$@"
 }
 
 #
@@ -459,7 +447,7 @@ cmd_summary() {
 	do
 		case "$1" in
 		--cached)
-			cached="$1"
+			cached=1
 			;;
 		--files)
 			files="$1"
@@ -509,7 +497,7 @@ cmd_status()
 	do
 		case "$1" in
 		-q|--quiet)
-			GIT_QUIET=1
+			quiet=1
 			;;
 		--cached)
 			cached=1
@@ -531,7 +519,7 @@ cmd_status()
 		shift
 	done
 
-	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper status ${GIT_QUIET:+--quiet} ${cached:+--cached} ${recursive:+--recursive} -- "$@"
+	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper status ${quiet:+--quiet} ${cached:+--cached} ${recursive:+--recursive} -- "$@"
 }
 #
 # Sync remote urls for submodules
@@ -544,7 +532,7 @@ cmd_sync()
 	do
 		case "$1" in
 		-q|--quiet)
-			GIT_QUIET=1
+			quiet=1
 			shift
 			;;
 		--recursive)
@@ -564,12 +552,12 @@ cmd_sync()
 		esac
 	done
 
-	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper sync ${GIT_QUIET:+--quiet} ${recursive:+--recursive} -- "$@"
+	git ${wt_prefix:+-C "$wt_prefix"} submodule--helper sync ${quiet:+--quiet} ${recursive:+--recursive} -- "$@"
 }
 
 cmd_absorbgitdirs()
 {
-	git submodule--helper absorb-git-dirs --prefix "$wt_prefix" "$@"
+	git submodule--helper absorbgitdirs --prefix "$wt_prefix" "$@"
 }
 
 # This loop parses the command line arguments to find the
@@ -585,18 +573,10 @@ do
 		command=$1
 		;;
 	-q|--quiet)
-		GIT_QUIET=1
-		;;
-	-b|--branch)
-		case "$2" in
-		'')
-			usage
-			;;
-		esac
-		branch="$2"; shift
+		quiet=1
 		;;
 	--cached)
-		cached="$1"
+		cached=1
 		;;
 	--)
 		break
@@ -622,12 +602,6 @@ then
     fi
 fi
 
-# "-b branch" is accepted only by "add" and "set-branch"
-if test -n "$branch" && (test "$command" != add || test "$command" != set-branch)
-then
-	usage
-fi
-
 # "--cached" is accepted only by "status" and "summary"
 if test -n "$cached" && test "$command" != status && test "$command" != summary
 then
diff --git a/submodule.c b/submodule.c
index 4e299f578f..2af16c647d 100644
--- a/submodule.c
+++ b/submodule.c
@@ -2374,7 +2374,7 @@ void absorb_git_dir_into_superproject(const char *path,
 		cp.no_stdin = 1;
 		strvec_pushl(&cp.args, "--super-prefix", sb.buf,
 			     "submodule--helper",
-			     "absorb-git-dirs", NULL);
+			     "absorbgitdirs", NULL);
 		prepare_submodule_repo_env(&cp.env);
 		if (run_command(&cp))
 			die(_("could not recurse into submodule '%s'"), path);
diff --git a/t/t7406-submodule-update.sh b/t/t7406-submodule-update.sh
index 43f779d751..06d804e213 100755
--- a/t/t7406-submodule-update.sh
+++ b/t/t7406-submodule-update.sh
@@ -1074,7 +1074,7 @@ test_expect_success 'submodule update --quiet passes quietness to merge/rebase'
 	 git submodule update --rebase --quiet >out 2>err &&
 	 test_must_be_empty out &&
 	 test_must_be_empty err &&
-	 git submodule update --rebase -v >out 2>err &&
+	 git submodule update --rebase >out 2>err &&
 	 test_file_not_empty out &&
 	 test_must_be_empty err
 	)