Ok, serious question: At cadences 120 and below, rider aged 50 and above, no previous racing or club experience, for the majority of those that fall into that group....is there an increase in power/efficiency/speed or anything that comes for (almost) free with clipping in?
I've always believed that the only advantage for most is the consistency of correct foot positioning w/ respect to the pedal, and that unweighting rather than up-stroking is what seperates the talented spinners from the rest.
Now as far as stiff shoes (vs non stiff but equally non-compressable soles) transfering more power.........?