I 6-putted Oakmont #2 on tourney speed greens - put my second shot above the hole, and when the putt slid by, it just kept going... approx 20feet past
Then, as i was putting back up the hill I hit it hard - too hard and pretty much ended up where I started.
Proving that I'm a slow learner, that putt also slid by and down the hill... can't remember what happened next, but ended with 6 putts !!!! It can happen...