http://sports.yahoo.com/golf/blog/devil_ball_golf/post/Davis-calls-penalty-on-himself-gives-up-shot-at?urn=golf,234963"Imagine standing on the edge of achieving your life's dream. You make a small mistake that will cost you your dream -- but if you don't say anything, you might just get away with it. Would you own up to the mistake, or would you keep quiet and hope for the best?"
"Davis's approach shot on the first hole of the playoff bounced off the green and nestled in among some weeds. (You can see the gunk he was hitting out of in that shot above.) When Davis tried to punch the ball up onto the green, his club may have grazed a stray weed on his backswing.
So what's the big deal? This: hitting any material around your ball during your backswing constitutes a violation of the rule against moving loose impediments, and is an immediate two-stroke penalty. And in a playoff, that means, in effect, game over"
"Okay, you can think that's a silly penalty or whatever, but that's not the point of this story. The point is that Davis actually called the violation on himself."