diff --git a/gtk2_ardour/editor_drag.cc b/gtk2_ardour/editor_drag.cc
index f949f3841a..21984c8eea 100644
--- a/gtk2_ardour/editor_drag.cc
+++ b/gtk2_ardour/editor_drag.cc
@@ -3393,6 +3393,10 @@ MeterMarkerDrag::start_grab (GdkEvent* event, Gdk::Cursor* cursor)
 {
 	Drag::start_grab (event, cursor);
 	show_verbose_cursor_time (adjusted_current_time (event));
+
+	/* setup thread-local tempo map ptr as a writable copy */
+
+	TempoMap::fetch_writable ();
 }
 
 void
@@ -3487,6 +3491,8 @@ MeterMarkerDrag::finished (GdkEvent* event, bool movement_occurred)
 		if (was_double_click()) {
 			_editor->edit_meter_marker (*_marker);
 		}
+		/* reset thread local tempo map to the original state */
+		TempoMap::fetch ();
 		return;
 	}
 
@@ -3495,11 +3501,14 @@ MeterMarkerDrag::finished (GdkEvent* event, bool movement_occurred)
 	_editor->set_snap_mode (_old_snap_mode);
 
 	TempoMap::SharedPtr map (TempoMap::use());
+	TempoMap::update (map);
 
-	XMLNode &after = map->get_state();
+	XMLNode &after = TempoMap::use()->get_state();
 	_editor->session()->add_command (new MementoCommand<Temporal::TempoMap> (new Temporal::TempoMap::MementoBinder(), before_state, &after));
 	_editor->commit_reversible_command ();
 
+	TempoMap::update (map);
+
 	// delete the dummy marker we used for visual representation while moving.
 	// a new visual marker will show up automatically.
 	delete _marker;
@@ -3508,6 +3517,9 @@ MeterMarkerDrag::finished (GdkEvent* event, bool movement_occurred)
 void
 MeterMarkerDrag::aborted (bool moved)
 {
+	/* reset thread local tempo map to the original state */
+	TempoMap::fetch ();
+
 	_marker->set_position (_marker->meter().time());
 
 	if (moved) {
@@ -3515,11 +3527,11 @@ MeterMarkerDrag::aborted (bool moved)
 		_editor->set_grid_to (_old_grid_type);
 		_editor->set_snap_mode (_old_snap_mode);
 
-		TempoMap::use()->set_state (*before_state, Stateful::current_state_version);
 		// delete the dummy marker we used for visual representation while moving.
 		// a new visual marker will show up automatically.
 		delete _marker;
 	}
+
 }
 
 TempoMarkerDrag::TempoMarkerDrag (Editor* e, ArdourCanvas::Item* i, bool c)
@@ -3562,7 +3574,6 @@ TempoMarkerDrag::setup_pointer_offset ()
 void
 TempoMarkerDrag::motion (GdkEvent* event, bool first_move)
 {
-
 	if (!_marker->tempo().active()) {
 		return;
 	}
@@ -3676,6 +3687,7 @@ TempoMarkerDrag::finished (GdkEvent* event, bool movement_occurred)
 	if (!_marker->tempo().active()) {
 		return;
 	}
+
 	if (!movement_occurred) {
 		if (was_double_click()) {
 			_editor->edit_tempo_marker (*_marker);
@@ -3692,14 +3704,9 @@ TempoMarkerDrag::finished (GdkEvent* event, bool movement_occurred)
 	/* push the current state of our writable map copy */
 
 	TempoMap::SharedPtr map (TempoMap::use());
-
 	TempoMap::update (map);
 
-	/* fetch it back into thre thread-local and locally-scoped ptrs */
-
-	map = TempoMap::fetch();
-
-	XMLNode &after = map->get_state();
+	XMLNode &after = TempoMap::use()->get_state();
 
 	_editor->session()->add_command (new MementoCommand<Temporal::TempoMap> (new Temporal::TempoMap::MementoBinder(), _before_state, &after));
 	_editor->commit_reversible_command ();
@@ -3712,15 +3719,15 @@ TempoMarkerDrag::finished (GdkEvent* event, bool movement_occurred)
 void
 TempoMarkerDrag::aborted (bool moved)
 {
-	// _point->end_float ();
-	_marker->set_position (timepos_t (_marker->tempo().beats()));
-
 	/* reset the per-thread tempo map ptr back to the current
 	 * official version
 	 */
 
 	TempoMap::fetch ();
 
+	// _point->end_float ();
+	_marker->set_position (timepos_t (_marker->tempo().beats()));
+
 	if (moved) {
 		// delete the dummy (hidden) marker we used for events while moving.
 		delete _marker;
diff --git a/gtk2_ardour/editor_ops.cc b/gtk2_ardour/editor_ops.cc
index d14df25140..16157db69f 100644
--- a/gtk2_ardour/editor_ops.cc
+++ b/gtk2_ardour/editor_ops.cc
@@ -7080,7 +7080,7 @@ Editor::define_one_bar (timepos_t const & start, timepos_t const & end)
 {
 	timecnt_t length = start.distance (end);
 
-	TempoMap::SharedPtr tmap (TempoMap::use());
+	TempoMap::SharedPtr tmap (TempoMap::write_copy());
 	const Meter& m (tmap->meter_at (start));
 
 	/* length = 1 bar */
@@ -7165,6 +7165,8 @@ Editor::define_one_bar (timepos_t const & start, timepos_t const & end)
 
 	_session->add_command (new MementoCommand<Temporal::TempoMap> (new Temporal::TempoMap::MementoBinder(), &before, &after));
 	commit_reversible_command ();
+
+	TempoMap::update (tmap);
 }
 
 void
@@ -8097,12 +8099,14 @@ Editor::insert_time (
 			begin_reversible_command (_("insert time"));
 			in_command = true;
 		}
-		TempoMap::SharedPtr tmap (TempoMap::use());
+		TempoMap::SharedPtr tmap (TempoMap::write_copy());
 
 		XMLNode& before (tmap->get_state());
 		tmap->insert_time (pos, samples);
 		XMLNode& after (tmap->get_state());
 		_session->add_command (new MementoCommand<Temporal::TempoMap> (new Temporal::TempoMap::MementoBinder(), &before, &after));
+
+		TempoMap::update (tmap);
 	}
 
 	if (in_command) {
@@ -8273,7 +8277,7 @@ Editor::remove_time (timepos_t const & pos, timecnt_t const & duration, InsertTi
 	}
 
 	if (tempo_too) {
-		TempoMap::SharedPtr tmap (TempoMap::use());
+		TempoMap::SharedPtr tmap (TempoMap::write_copy());
 		XMLNode& before (tmap->get_state());
 
 		if (tmap->remove_time (pos, duration)) {
@@ -8283,6 +8287,8 @@ Editor::remove_time (timepos_t const & pos, timecnt_t const & duration, InsertTi
 			}
 			XMLNode& after (tmap->get_state());
 			_session->add_command (new MementoCommand<Temporal::TempoMap> (new Temporal::TempoMap::MementoBinder(), &before, &after));
+
+			TempoMap::update (tmap);
 		}
 	}
 
diff --git a/gtk2_ardour/editor_tempodisplay.cc b/gtk2_ardour/editor_tempodisplay.cc
index e6be305562..3dcb58996f 100644
--- a/gtk2_ardour/editor_tempodisplay.cc
+++ b/gtk2_ardour/editor_tempodisplay.cc
@@ -443,7 +443,7 @@ Editor::mouse_add_new_meter_event (timepos_t pos)
 		return;
 	}
 
-	TempoMap::SharedPtr map (TempoMap::use());
+	TempoMap::SharedPtr map (TempoMap::write_copy());
 	MeterDialog meter_dialog (map, pos, _("add"));
 
 	switch (meter_dialog.run ()) {
@@ -476,6 +476,8 @@ Editor::mouse_add_new_meter_event (timepos_t pos)
 	_session->add_command (new MementoCommand<Temporal::TempoMap> (new Temporal::TempoMap::MementoBinder(), &before, &map->get_state()));
 	commit_reversible_command ();
 
+	TempoMap::update (map);
+
 	//map.dump (cerr);
 }
 
@@ -521,7 +523,7 @@ Editor::edit_meter_section (Temporal::MeterPoint& section)
 	Temporal::BBT_Time when;
 	meter_dialog.get_bbt_time (when);
 
-	TempoMap::SharedPtr tmap (TempoMap::use());
+	TempoMap::SharedPtr tmap (TempoMap::write_copy());
 
 	begin_reversible_command (_("replace meter mark"));
 	XMLNode &before = tmap->get_state();
@@ -531,6 +533,8 @@ Editor::edit_meter_section (Temporal::MeterPoint& section)
 	XMLNode &after = tmap->get_state();
 	_session->add_command (new MementoCommand<Temporal::TempoMap> (new Temporal::TempoMap::MementoBinder(), &before, &after));
 	commit_reversible_command ();
+
+	TempoMap::update (tmap);
 }
 
 void
@@ -551,7 +555,7 @@ Editor::edit_tempo_section (TempoPoint& section)
 	bpm = max (0.01, bpm);
 	const Tempo tempo (bpm, nt, end_bpm);
 
-	TempoMap::SharedPtr tmap (TempoMap::use());
+	TempoMap::SharedPtr tmap (TempoMap::write_copy());
 
 	Temporal::BBT_Time when;
 	tempo_dialog.get_bbt_time (when);
@@ -564,6 +568,8 @@ Editor::edit_tempo_section (TempoPoint& section)
 	XMLNode &after = tmap->get_state();
 	_session->add_command (new MementoCommand<Temporal::TempoMap> (new Temporal::TempoMap::MementoBinder(), &before, &after));
 	commit_reversible_command ();
+
+	TempoMap::update (tmap);
 }
 
 void
@@ -582,13 +588,15 @@ gint
 Editor::real_remove_tempo_marker (TempoPoint *section)
 {
 	begin_reversible_command (_("remove tempo mark"));
-	TempoMap::SharedPtr tmap (TempoMap::use());
+	TempoMap::SharedPtr tmap (TempoMap::write_copy());
 	XMLNode &before = tmap->get_state();
 	tmap->remove_tempo (*section);
 	XMLNode &after = tmap->get_state();
 	_session->add_command (new MementoCommand<Temporal::TempoMap> (new Temporal::TempoMap::MementoBinder(), &before, &after));
 	commit_reversible_command ();
 
+	TempoMap::update (tmap);
+
 	return FALSE;
 }
 
@@ -617,12 +625,14 @@ gint
 Editor::real_remove_meter_marker (Temporal::MeterPoint *section)
 {
 	begin_reversible_command (_("remove tempo mark"));
-	TempoMap::SharedPtr tmap (TempoMap::use());
+	TempoMap::SharedPtr tmap (TempoMap::write_copy());
 	XMLNode &before = tmap->get_state();
 	tmap->remove_meter (*section);
 	XMLNode &after = tmap->get_state();
 	_session->add_command (new MementoCommand<Temporal::TempoMap> (new Temporal::TempoMap::MementoBinder(), &before, &after));
 	commit_reversible_command ();
 
+	TempoMap::update (tmap);
+
 	return FALSE;
 }