I'm fast, especially when showing off, but have lost some skin over the years. I shave the root end off, smash between the cutting board and flat knife side, remove the skins, then chop furiously with a rocking of the knife from tip to bolster. I move the knife around by holding the tip with one hand, and moving the handle with the other. The tip of the knife remains planted on the cutting board. After a few chops, I move the tip and repeat. Usually, I chop multiple cloves at the same time. I'm really mincing the garlic. I do the same when mincing other veggies and such.
Seeeeeeya; Goodweed of the North