I don't think I broke the redstone, so it may still be running.
In vanilla, I made a piston that would extend and rectract on an uncovered block. The lag was horrendous. I got down to 0 fps before the F3+C worked. I can upload the world if you want me to.
Also, root.tick.keyboard lags when you break the block.
I don't think I broke the redstone, so it may still be running.