Move count enhancement lost with speed enhancement commit #4
Description
Commit 1758e31 improved moves per piece (especially at sizes around 70 or so), but the very next commit, b00b79f, undid those changes. I recommend remaking the changes from the move count enhancement pull request, so a full face is copied in a scan rather than just a quadrant. (Use start of 1, not Mid; make the mstack a bit larger; and make the c loop go up to R1 instead of Mid.)