I had a similar problem. The pressure of peddling on the drive side pushes the front of the rear wheel to the left. No matter how tight I made the quick release (and yes I do know how to use them) it continued to happen although the tighter I made it the less severe or less it moved. Someone suggested using a Shimano skewer, which I happened to have, and it solved the problem. I still have to make the skewer pretty tight but it works properly. If you go on ebay you can pick up a set of skewers pretty cheaply. Probably for under $20. The skewer I had around was a cheap Tiagra/105 level so you don't need a Dura Ace level. The Shimino have an internal cam system which I guess is tighter.