Oh and one other detail. Turning ones toes inward was also highly recommended.
I never heard of that, but I was not a racer and never tried to study what they were doing.
I like to have some float in my shoes with cleats, but I think none of my shoes or pedals allow enough float to accomplish that.
I'm in the same boat as you in that I don't fully know why but it did seem to work in. my sprint speed. I think it has something to do with using more of the outside part of the muscle and as you turn your feet in just a bit, your thighs and knees are right next to the top tube. I think it has a more direct line of pressure - just imagine the opposite taken to an extreme, cycling with the knees spread out and how inefficient that is. I once was told by someone else that it is also more aero-dynamic, but cycling is full of exagerations. At my speeds today - what's aero-anything got to do with it. 
Was there not a gent on this forum from New Zealand who raced at international levels here? I can't remember his name, but I'd love to hear from him as to whether what I've said has any merit.
I recall reading several years ago that time trial competition at the international level also meant putting knees close to the top tube for aero purposes. And when you think about some of the speeds the pros achieve in a time trial, I can see how aero concerns would be very important. That said, I still would think that such a posture would impair maximizing muscle power. But if they balance that in a wind tunnel, I could see some optimum position that has good muscle power and a better aero position.
My only attempts at aero are to use the drops on my drop bars in head winds, but the tops of my bars are almost as high as the top of my saddle, so the drops on my touring bikes are probably up higher than the handlebar tops on racing bikes. Headwinds are the reason that I have drop bars on my Nomad Mk II, which is against the advice from Thorn.
