Pumping legs full of chemicals. Then wrapping them up tight in saran wrap and diesel fuel till they are burning hot. All so they are in too much pain to stand on, for more leg action?
I guess there is worse. I mean sure there is.
But there is never a time when soring isn't thought of as abusive in my book.
I don't know if I'd compare HYPP to soring beyond the fact that humans keep doing both. Breeding HYPP positive horses to make those gross halter horses or stuffed their TWH's legs full of embalming fluid so they burn and they move faster.
Really why compare? It all kinda sucks don't it?