On this forum we often advocate trying different things when you get stuck. Different pick grips, different hand/arm postures and so on.
Here’s an example in this spirit from me: I randomly stumbled on this variation of my USX motion while fiddling with a bass (I can’t play bass beyond playing chord tonics!).
The very different posture and placement of my right hand made something click, and I recorded what I think is my fast tremolo ever. The fastest stretches are approximately 16th notes @225bpm, which I didn’t think I could do:
Take1 (probably faster but less controlled):
Take 2 (probably slower but more controlled):
Disclaimer 1: I don’t feel in control of this movement and it feels tiring and tense. But Maybe it can get better as I get familiar with it and eliminate the little random variations in muscle activation etc.
Disclaimer 2: I can only access this specific motion on the A string of a bass. Haven’t figured out yet how to transfer this to a guitar.
Comments / advice welcome