Where's the evidence that properly done up QRs are getting forced out of dropouts by disk brakes?
What evidence do you want?
How do you prove, after the wheel has come out, that the QR was ever done up properly in the first place?
Most deniers seem to take the line that they know it can't happen, so the person who's had their wheel come out must be wrong/lying when they say they had done the QR up properly.
I use rim brakes, but it did happen to a friend pulling up into Briancon campsite after dropping off the Galibier. On a bike new from Longstaff a couple of weeks before, that he'd never taken the front wheel out of. Everything else on the bike, including the rear QR, was done up gorilla-tight.
Dead lucky in one way - at a speed slow enough so it was just minor grazes, on the edge of the only town we passed through that had a good enough bike shop to sell him a new set of forks.
