Its called jittering , most of the time I always combo people using straight line , speed clicking in Minecraft. Jittering doesn't make you good it has a little cooldown for like 0.6 seconds? But the way he combos you is his clicks. This is already a Minecraft PE thing when 1.1.5 Ver Started, They made hit registration more good and much better orrr whatever. You can't do this if your playing mobile / PE Because you can't click on air or you know tapping on everywhere you want without using reach. I'm not sure if I'm right but I think this would help!