I mash and I pull up. The cleats give me a lot more POWER for my cadence. I don't know if it is bad for my knees, but since going clipless, my annual mileage has gone up and my knee pain has gone down (also maybe 20 or 30 lbs weight loss). Even some speed gains in the last year.

One of the reasons I chose to go clipless was that I was finding on longer rides with casual shoes and toeclips, my feet were tilting to the outside, and it seemed problematic. Plus uncomfortable pressure points on the feet from the rattrap style pedals. The clipless shoes/pedals are generally comfortable, and keep the feet flat and square. All of which seem good.