I have a personal theory (based on the graphs from the reports from both crashes) that once the stabilisers go far enough out of trim at high enough speeds, tha

I have a personal theory (based on the graphs from the reports from both crashes) that once the stabilisers go far enough out of trim at high enough speeds, that the even electric trim motor isn't powerful enough to move the stabiliser. In both crashes, after repeated activations of MCAS has pushed the stabiliser almost fully down, we see the pilots do two quick presses of the trim up button. The graph shows the stabiliser barely moving (much less than a press of the same length earlier in the flight). I suspect the pilots pressed the trim up button, heard a loud noise from the electric motor straining, or a fuse popping, or something? So they stopped pressing trim up. Even worse, only trim up was failing, MCAS was still able to command more trim down.