Originally Posted by
pallen
Again, he's talking about studying pedaling techniques, not platform vs clipless pedals and he's studying output in steady state cruising.
Yes, he's talking about pedaling techniques.
No, he is not talking about "steady state cruising." He's discussing the full range of riding circumstances, including track racing, climbing, sprinting and off-road. ("...force-measuring pedals show us that no cyclists, not even track pursuiters who are capable of silky-smooth pedal strokes at 130 rpm, really exert upward force when the pedal is coming up from dead bottom center.")
And the point, again, is that even with clipless, you are not applying force to the drivetrain on the upstroke (as the OP mistakenly suggests). This is a myth based on subjective experiences, and there is no evidence to support it.
Put those test subjects on a 15% grade and I guarantee you there will be a significant amount of "pulling up" going on.
No, what's happening is you are basically lifting your leg. The feeling of a tiny tug on the upstroke does not mean you are pouring watts into the drivetrain at that moment.
There are also at least two studies which indicate that intentionally pulling on the upstroke reduces total (gross) efficiency.
http://www.ncbi.nlm.nih.gov/pubmed/17545890
http://www.ncbi.nlm.nih.gov/pubmed/18418807
That type of pedal stroke may be useful as a training technique to develop a smoother stroke, but it are not what you want to do when actually riding.
This is not to say that clipless offers zero benefits. It's that the benefit is control and ride feel, not power output.