Horse books/movies do it too. In National Velvet, Velvet is coached by the curmudgeonly Mickey Rooney. In The Black Stallion, Alec is coached by the still adorably grouchy Mickey Rooney. In Sylvester, a grizzled old coot is caught schooling haute ecole in the moonlight.
It's all very wax on, wax off.
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It wasn't long before I came to associate crabby/crusty with knowledge. But sometimes under the crusty exterior there's just even more manure.
The entertainment value, of course, is infinite. There was the barn owner who thought ground manners were optional and wanted me to do turn in/ turn out of her (Brontosaurus Equus) warmblood herd. One day she admitted, in hushed tones, that even she was a little afraid of the worst offender. There was the bra-optional lady who made me ride in a western saddle with miles-long stirrups that just wouldn't adjust. There was the hoarder obsessed with goats.
There's even one I've never met - a horse trainer in my area that used to own my dog before he found his way into our home. Have you ever seen a hundred pound dog cringe at everyday things like brooms and hoses? I have. So, my fate has been sealed. I'm already a bit eccentric and crusty too I guess. Next stop, crazy! If I ever cross paths with that walking turd of a trainer, I will go crazy. Foaming at the mouth, get-in-the-ring crazy. Anything less, I imagine, would be un-equestrian.