I finally bought clippers. Just a cheapy pair, less than $50 for trimming Gwyn's mane, dock, fetlocks (maybe), (never muzzle, she will be au naturale forevah) and the occasional trace clip (I think it could handle not a whole body thing).
Tonight, we practiced desensitization with the clippers.
I can't remember if Gwyn has been clipped before. I don't think she has but you wouldn't know it. After her dinner I put her in the cross ties and turned on the clippers. She flicked an ear at me but otherwise didn't react. With the free hand I stroked her shoulder.
Then I brought the clippers near her body. She definitely had ears on me and twitched when I touched the buzzing clippers to her shoulder (but no clipping). Then she relaxed and I kept petting and talking to her.
Then I tried a quick buzz on her neck with the actual blades. No big.
Then I clipped her damn bridle path all proper like and tidied up the hack job roach I did to her mane.
It was no big deal.
I fucking love this horse.
Have some photos from 3 days ago when the fog settled in while I was feeding.