As a personal comment on the fixed/SS helping with bouncing, my experience is that it hurts more than helps. I started riding my single speed much more, to force myself to stand more often (I tend to sit too much on my geared bike). Well, I stand much more, and can spin much higher without bouncing, but I have trained myself to be faster on my single speed than I am on my geared bike. I use the gears to keep my cadence higher, but put much less force on the pedals. And I still never stand on the geared bike. They are two very different riding styles, and I don't think that as much crosses over as you might think. Or I am untrainable.