[icontrolyourworld]

get a flat keyboard to start out it'll help finding that balance between bottoming the key vs. actuating the key

when a fast jackhammer comes up start hitting it ahead of time before it hits the receptor so that by the end of the time the jack is finished you'll have hit the necessary or close to amount of jack needed.

whatever speed you're at now for vibro just try and work your way up to whatever speed you need using this method. it's completely not about accuracy until way later, it's most important to just get the needed amount of actions in per second. also don't be afraid to mash patterns that are too hard, controlled mashing and vibro have similar concepts so that's why you might often find these paired in files.