It looks the same to you, but it isn’t.
Here’s the scoop:
The pace is a lateral two-beat gait. In the pace, the two legs on the same side of the horse move forward together, unlike the trot, where the two legs diagonally opposite from each other move forward together.
In both the pace and the trot, two feet are always off the ground.
If you aren’t a racing enthusiast — specifically of sulky racing — or just a casual horse rider, this isn’t going to really matter much. But if you are a trainer for trotting horses, pacers and trotters are not allowed on the same course. And if you are planning on an equestrian career, how the horse leads at a trot (or pace) matters and you have to know how to get your horse to shift leads.
I could sometimes do it instinctively but never learned to do it intentionally. I wasn’t that good.
I used to ride, but to be fair, I never really cared much about which feet were doing what. If I were jumping or in competition, I would have cared, but for the purposes of most riders, this is not all that critical.
Or maybe it is and I just never got technical enough about the movement of horses to know the difference?
Bet you thought this was going to be about pacing the floor or something, didn’t you. Hah!