Whatever, I've known plenty of thoroughbreds or similarly sensitive horses that simply aren't a huge fan of the grooming process.
I had written it off.
Until one day I was super limited on time and he was my last horse of the day and I just took him up to the arena to longe him without (gasp) grooming beforehand.
I reel him in when my phone rings after he'd been trotting around and over poles for a few minutes. He's a little warm, but certainly not remotely approaching sweaty.
Absently, while catching up with my mom, I start scratching him.
He indicated that he was enjoying being vigorously scratched.
Perplexed, I repeated the experiment the following day. It appears that if lightly lunged before grooming, this horse THOROUGHLY loves a good grooming with scratchy curries and soft dandy brushes. Whodathunk. Any theories as to why that might be?