The gait you mentioned,does he move his legs laterally (both legs on the same side moving at same time) or diagonally (one leg on each side moving at same time)? If they're moving laterally,then he is probably "pacing". My neighbors used to have a retired Standardbred racer that I exercised for them who paced,and it was SO smooth! Felt a little strange at first,but once you get the rhythm it is a super smooth ride that covers ground quickly. Seeing your guy makes me miss those rides!