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i am curious, is the speedplay cleat fundamentally differently shaped when attached to a 4-hole shoe, vs. a 3-hole shoe? anyone know?
i am a little skeptical of these wind tunnel results. because while speedplay pedals are indeed quite small, the speedplay cleat is really enormous, so it seems to me that any so-called drag savings would basically be zero, or maybe 1-2 sec over a 40km TT. anyone have any thoughts? or am i missing something?
my understanding is that with a 4 hole shoe, the cleat mounts directly to the shoe, with a 3 hole shoe, the speedplay cleat needs an adapter which adds about 4-7mm? of height.
http://www.lakecycling.com/...-speedplay-p-69.html 
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