Okay, I've seen this a few times now. A horse entered in an event that has something like 'Exceptional Quality Saddle' (or another item) set as the rider. Here is a screenshot of one that I just saw: Link
The horses there are owned by different players, but they both say 'Prescription to cure horse for condition or injury.' for the rider.
Are the NPCs named this just for kicks or is it some kind of glitch or something?
I don't know if it effects placings or anything, but it's really bugging me (no pun intended).
Has anybody else noticed this?