Proof would be incredibly difficult without a large # of participants, with a distribution of normal and marathon players (to remove bias from switching speeds and being unfamiliar with the new one). You'd also need to play enough maps with all of those players until you got a feel that the outcomes were not dependent on the map (spawning next to shaka on marathon is very different from spawning next to frederick). On top of ALL OF THAT, we'd have to control for difficulty level, because damned if that couldn't make a difference too

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I definitely find marathon easier, or used to. Now, it's harder for me to say it, because I can beat immortal pretty often on anything but quick, while I can't beat deity without supreme cheese on anything...but deity is so much harder than immortal that it's going to trump speed variance. That deity is hard is non-argument, but it's oppressively so

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