I’m not sure if this is helpful (or even that good!) but I recorded some tremolo stuff. The metronome was at 300bpm. I included the slowed-down example (no video, sorry! But it’s the same audio from the first video… just slow)
It’s a little inconsistent slowed down, which I’m not surprised about. However, if I were to ever use something of this speed in a song, it’d be more for an effect than anything, so the slight inconsistency wouldn’t bother me that much.
Interestingly I find this extremely difficult unless I clench my fist in the way I do in this video. No idea why, but it’s far more uncontrolled without doing that (but still possible at a push.) This speed is reasonably comfortable. I couldn’t do if for anything much longer than the first example, but I probably wouldn’t want to.
Anyway, would be interesting to hear your thoughts.