Tried something completely different yesterday.  Ground work fine.  Consistently more responsive.  When I think back to how we were when we started groundwork and how we are now the progress is obvious.  Much room for improvement of course but it's good.  As for the riding, decided to ride one handed on a loose rein around the arena.  His job to stay on course and at the speed requested.  My job to leave him alone unless he needed bringing back on course or a reminder to maintain gait.  Clearly illustrated something.  If I left him alone he trotted along quite happily.  As soon as I touched the reins to bring him back to the arena boundary or to keep him from cutting a corner, down would go the head, nose pointing to the chest.  I could feel him mentally leave me as he went to that safe place of his where he outwardly complies with a request and inwardly shuts down.  So we played with walking and trotting around the arena - no cantering yet.  Asked him to halt with my seat from a big trot.  Really sat down on him and by gum, we had a perfectly square halt.  Hopped off with lots of praise.  But the best part was yet to come.  Took him out for pick.  I can loop the lead rope over his withers while he eats so he has a bit of freedom.  When it was time to quit I walked down the road toward the driveway.  Called him.  He looked up but didn't come.   I walked a bit further and called again.  He'd been watching me while grazing, both ears pricked.  When I called his head snapped up and on he came at the gallop.  The gallop turned into a trot but he did trot all the way to me.  Gave him a big hug.  What a lovely feeling.  I know if I called him while he felt safe in his own paddock he wouldn't have left the other horses to come.  Nevertheless I glowed the rest of the day.