I just finished up a Matt Flinner course and he (among many others) thinks in cut time (2/2) while you and I think in common time (4/4). It's funny because I have heard heated arguments about which is proper. Six of one and a half dozen of the other. So Matt's 100bpm is our 200bpm.
I am completely unable to figure this out. All I know that setting Strum Machine to 100 \is the same speed as if I set a metronome to 200 bpm with each tick a quarter note. So yeah, when I said before that I had played a song at 200, Strum Machine was set to 100. Strum machine at 200 would be, what, almost 7 beats a second. Maybe some professional could do that but I sure can't.