The pulling up effect for me only happens if I'm out of the saddle pushing really hard - even then its minimal. I do feel like I get a slightly longer power stroke clipped in. Pedaling is a little more efficient, but equally important is the fact that you are connected to you pedals. The annoyance of having to clip in is offset by having your feet attached. Even though I rarely had problems with slipping before, there is a noticeably more secure feeling with the clipless pedals. I still ride on platforms from time to time, but the difference in feel is a fairly dramatic difference.