[jacobvl39]

Well, you won't like to hear this but your best bet is to switch to a standard spread playstyle. You'll lose your muscle memory at first but you will eventually re-gain it and in the long run it's an easier and more effective way to play.

As you mentioned, 3-4 trills are going to be a problem but jumptrills might be an even bigger one. Once you get into the higher levels, fast jumptrills ([12][34][12][34] etc.) become very common and with a split layout you will need to OHT the whole thing.

I know of one player who is near d6 with almost 2000 AAAs using split but he's the only one I'm aware of. So it is possible to get pretty good with split but not many people have done it, and I suspect this player would be ranked even higher if he played spread.

If you really don't want to switch, you'll need to practice the 3-4 trilling motion on its own and get comfortable with it. You want to keep your wrist relaxed, a healthy curvature in the hand and fingers, and the majority of the movement should come from a small back-and-forth rotation of the wrist. Your fingers should be moving up and down a little bit -- don't keep them stiff or tense. I'd aim for about 75% of the force coming from wrist rotation and 25% from finger flexion. You should be using the minimum degree of movement and force needed to depress the key, since anything more is wasted energy. If you find yourself tensing up, lifting your fingers more than a tiny bit, or trilling unevenly then you need to slow down and work on finding a more comfortable motion and locking in into muscle memory. Gradually speed it up when you're ready. The biggest gains in stamina are not from using more muscle, but from using efficient movement patterns and conserving energy.