Oh, can I relate to this one! LOL My fave horse to ride also has this habit. I take credit for it as I really didn’t cement the “stand still” cue firmly enough when he was young (I’ve owned him since he was born and he’s 16 now). It got worse when he had an undiagnosed rib injury, and it was a bugger to undo. He’s much better now. What I’ve done is found the one routine that seems to keep him happy. Instead of coming at the block from the front by his shoulder as would be the usual approach, I drop the reins on his neck, come at the block from his hip, and rub his butt and scratch it while I’m getting ready to mount. Apparently that’s his sweet spot, because most times he will stand beautifully now (assuming his lady love isn’t in heat and yelling from the pasture, then it might take a circle or two).
Now, this is just what worked for MY horse. I had already tried all of the other suggestions from trainers and fellow horse peeps, and I came upon this by accident. I’m sure it looks silly, but it works, and that’s my goal. You have to find your horse’s currency–what he’ll accept in trade for the behavior you’re trying to elicit, in this case standing still.
It’s a lot easier to implant a habit than to remove it, and the primary reason for that is that intermittent reinforcement (disciplining him in a less than consistent way) makes the habit stronger. It’s like a child acting out to get his favorite treat. Reinforce it only once, and you’ve got a kid who will test over and over and over again to see if THIS is the time it’ll work. So whatever you try, it needs to be absolutely 100% consistent. There can’t be any “Well, he’s nervous today”. There has to be total focus on getting past this one issue.
And keep in mind that you need to focus on the behavior you WANT in the simplest terms possible as opposed to the bazillion you DON’T want. Don’t make him guess by punishing errors. Only reinforce the correct behavior. Between errors are resets. Keep resetting until he gets exactly what you’re asking, and then your training efforts should fly. I love the clicker for this.
Horses In the Yard