I think you just have to keep doing it. He ripped himself apart doing that windmill thing. If you watch him at Monterey, I think it's Monterey, he's got blood on his face cuz he ripped a nail off doing that windmill! Now that's rock and roll!
Pete in his own words:
It is terribly painful. But I'm used to the fact that there will be pain. I know that I will take my nail off at the beginning of every tour. Still. The string gets under the fingernails and rips it off. It's part of the job. I am playing sometimes and I go do a windmill , "Wang, wang, wang, blood" and then I think, This is it. I've arrived. It is the place where I should be, like a boxer in the middle of a fight.
And when he injured himself in '89 from the windmill:
Yeah. That time I speared myself. I was using a guitar that was created for Eric Clapton. It had one of those whammy bars for vibrato, basically a sharp piece of metal. It went in one side of my hand and out the other. I lifted my arm and the guitar was hanging there by piece of metal through my hand.
PLAYBOY: Did you finish the show?
TOWNSHEND: I slipped it off and belted a lot, but yeah. And there was a brilliant surgeon nearby and I was lucky enough not to have hit anything vital. Then it happened again on the bike. Everything has happened to the same hand. I have some heavy right-hand karma. I've 126 stitches in my hand.
It's when he whips his arm around in a giant circle a few times (like the blade of a windmill) and then hits the strings playing a power chord. It's very cool. Here's a couple of pics with Pete in action:
Pete has said that he often breaks a string on the very first chord of the very first song of a performance "windmilling" - not as inconvenient (or painful) as sticking a vibrato arm right through your hand though!!