It happens frequently at the H/J shows locally. Most of them just combine classes & pin separately. Though, as I mentioned somewhere up thread, if it were me, I’d send him to shows I wasn’t taking clients to, even if it meant he had to drive further. And here’s why:
On COTH, most posters are well-educated in the rules governing H/J & can say, “No, that isn’t sketchy. They’re actually doing it because of a difficulty arising from rule xyz.” The parents & low level AA clients paying the bills for most trainers aren’t so familiar with the rules. Children & adults competing in the same class just doesn’t happen in most sports. (In my sport, a 16yo could theoretically enter lower level adult classes. Virtually never happens though, as 9 out of 10 the teen would get their a$$ kicked. They just stay in juniors until they age out at 18.) Yeah, I could explain the rules. But it is an uphill battle in business to overcome that initial taint of suspicion. Worse yet are the clients who might see & NOT say anything, giving me no chance to clarify. I potentially stand to lose the worth of the sale horse several times over.
@outside_leg, we were in frantic lease horse search mode all last month. It isn’t hard to gather info about a non-professional rider. I’ve heard of a lot of the AA by 6 degrees. My child can give you a complete rundown of any junior Hunter rider of note in the US. Lol. So with ponies; I can usually pinpoint when in their show career they transitioned to being ridden by a “normal” pony jockey. Anyone I’m unfamiliar with I can simply plug in their USEF # from the horse’s record & see more. Additionally, while my child may disagree 
, I do know enough about what I’m looking at to make a reasonably accurate judgment of rider skill influencing the horse’s way of going from watching a video of a course.
