diff --git a/gtk2_ardour/region_view.cc b/gtk2_ardour/region_view.cc
index b7828de9b3..4d45c158f7 100644
--- a/gtk2_ardour/region_view.cc
+++ b/gtk2_ardour/region_view.cc
@@ -1193,13 +1193,13 @@ RegionView::snap_region_time_to_region_time (timepos_t const & x, bool ensure_sn
 timecnt_t
 RegionView::region_relative_distance (timecnt_t const & duration, Temporal::TimeDomain domain)
 {
-	return Temporal::TempoMap::use()->full_duration_at (_region->position(), duration, domain);
+	return Temporal::TempoMap::use()->convert_duration (duration, _region->position(), domain);
 }
 
 timecnt_t
 RegionView::source_relative_distance (timecnt_t const & duration, Temporal::TimeDomain domain)
 {
-	return Temporal::TempoMap::use()->full_duration_at (_region->source_position(), duration, domain);
+	return Temporal::TempoMap::use()->convert_duration (duration, _region->source_position(), domain);
 }
 
 void
diff --git a/libs/temporal/tempo.cc b/libs/temporal/tempo.cc
index 9846aee288..9a2527e98d 100644
--- a/libs/temporal/tempo.cc
+++ b/libs/temporal/tempo.cc
@@ -2385,7 +2385,7 @@ TempoMap::bbt_duration_at (timepos_t const & pos, BBT_Offset const & dur) const
  */
 
 timecnt_t
-TempoMap::full_duration_at (timepos_t const & pos, timecnt_t const & duration, TimeDomain return_domain) const
+TempoMap::convert_duration (timecnt_t const & duration, timepos_t const & new_position, TimeDomain return_domain) const
 {
 	timepos_t p (return_domain);
 	Beats b;
@@ -2393,7 +2393,7 @@ TempoMap::full_duration_at (timepos_t const & pos, timecnt_t const & duration, T
 
 	if (return_domain == duration.time_domain()) {
 		/* new timecnt_t: same distance, but new position */
-		return timecnt_t (duration.distance(), pos);
+		return timecnt_t (duration.distance(), new_position);
 	}
 
 	switch (return_domain) {
@@ -2404,14 +2404,14 @@ TempoMap::full_duration_at (timepos_t const & pos, timecnt_t const & duration, T
 			break;
 		case BeatTime:
 			/* duration is in beats but we're asked to return superclocks */
-			switch (pos.time_domain()) {
+			switch (new_position.time_domain()) {
 			case BeatTime:
-				/* pos is already in beats */
-				p = pos;
+				/* new_position is already in beats */
+				p = new_position;
 				break;
 			case AudioTime:
 				/* Determine beats at sc pos, so that we can add beats */
-				p = timepos_t (metric_at (pos).quarters_at_superclock (pos.superclocks()));
+				p = timepos_t (metric_at (new_position).quarters_at_superclock (new_position.superclocks()));
 				break;
 			}
 			/* add beats */
@@ -2419,7 +2419,7 @@ TempoMap::full_duration_at (timepos_t const & pos, timecnt_t const & duration, T
 			/* determine superclocks */
 			s = metric_at (p).superclock_at (p.beats());
 			/* return duration in sc */
-			return timecnt_t::from_superclock (s - pos.superclocks(), pos);
+			return timecnt_t::from_superclock (s - new_position.superclocks(), new_position);
 			break;
 		}
 		break;
@@ -2428,14 +2428,14 @@ TempoMap::full_duration_at (timepos_t const & pos, timecnt_t const & duration, T
 		switch (duration.time_domain()) {
 		case AudioTime:
 			/* duration is in superclocks but we're asked to return beats */
-			switch (pos.time_domain ()) {
+			switch (new_position.time_domain ()) {
 			case AudioTime:
 				/* pos is already in superclocks */
-				p = pos;
+				p = new_position;
 				break;
 			case BeatTime:
 				/* determined sc at beat position so we can add superclocks */
-				p = timepos_t (metric_at (pos).sample_at (pos.beats()));
+				p = timepos_t (metric_at (new_position).sample_at (new_position.beats()));
 				break;
 			}
 			/* add superclocks */
@@ -2443,7 +2443,7 @@ TempoMap::full_duration_at (timepos_t const & pos, timecnt_t const & duration, T
 			/* determine beats */
 			b = metric_at (p).quarters_at_superclock (p.superclocks());
 			/* return duration in beats */
-			return timecnt_t (b - pos.beats(), pos);
+			return timecnt_t (b - new_position.beats(), new_position);
 			break;
 		case BeatTime:
 			/*NOTREACHED*/
diff --git a/libs/temporal/temporal/tempo.h b/libs/temporal/temporal/tempo.h
index 0fb8f30d1b..a5b7ac9895 100644
--- a/libs/temporal/temporal/tempo.h
+++ b/libs/temporal/temporal/tempo.h
@@ -782,7 +782,7 @@ class LIBTEMPORAL_API TempoMap : public PBD::StatefulDestructible
 	timecnt_t bbt_duration_at (timepos_t const & pos, BBT_Offset const & bbt) const;
 	Beats bbtwalk_to_quarters (Beats const & start, BBT_Offset const & distance) const;
 
-	Temporal::timecnt_t full_duration_at (Temporal::timepos_t const &, Temporal::timecnt_t const & duration, Temporal::TimeDomain domain) const;
+	Temporal::timecnt_t convert_duration (Temporal::timecnt_t const & duration, Temporal::timepos_t const &, Temporal::TimeDomain domain) const;
 
 	BBT_Time bbt_walk (BBT_Time const &, BBT_Offset const &) const;
 
diff --git a/libs/temporal/timeline.cc b/libs/temporal/timeline.cc
index 65789989fa..d273abbd83 100644
--- a/libs/temporal/timeline.cc
+++ b/libs/temporal/timeline.cc
@@ -169,14 +169,14 @@ timecnt_t::compute_superclocks() const
 {
 	assert (_distance.flagged());
 	TempoMap::SharedPtr tm (TempoMap::use());
-	return tm->full_duration_at (_position, *this, AudioTime).superclocks();
+	return tm->convert_duration (*this, _position, AudioTime).superclocks();
 }
 
 Beats
 timecnt_t::compute_beats() const
 {
 	assert (!_distance.flagged());
-	return TempoMap::use()->full_duration_at (_position, *this, BeatTime).beats();
+	return TempoMap::use()->convert_duration (*this, _position, BeatTime).beats();
 }
 
 timecnt_t