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@gbj_tester
Glad we got that sorted. You're both wrong.
If gain ratio is held constant, crank length is irrelevant over a wide range. It's irrelevant to acceleration rate, and irrelevant to constant speed cycling. Fuck, even Archimedes got this 2000 years before bicycle cranks were even invented; if you make the lever longer, you don't have to push as hard but you have to push further. The surprising thing is not that this has been proven time and again in laboratory tests, but that anybody would ever have thought otherwise. You don't get owt for nowt.
Not only that, but changing crank length while holding gain ratio constant isn't even changing our load/speed regime; for a given power output and a given gain ratio, pedal pressure and foot speed are constant. All we are changing, very slightly, is [1] the range of angular articulation in the leg joints, typically making far less difference to any individual by traversing the full range of commonly available crank lengths than we are imposing on different individuals by manufacturing such a narrow range and [2] the repetition rate, again over such a narrow range that nobody has been able to determine any significant difference.