I didn't really use a computer until my 1st year in college. And I didn't own a computer until I was 19, so I didn't learn to play FPS until I was in my 20's.

I didn't really use a computer until my 1st year in college. And I didn't own a computer until I was 19, so I didn't learn to play FPS until I was in my 20's. Before using WASD, I used WER and Space key for movement. Q=Jump, W=Forward, E=Strafe Left, R=Strafe Right. This allowed me to easily reach the number row and remap T=Chat 123456ASDFG for switching weapons and game controls. I switched to WASD with World of Warcraft, and use that for everything now mostly out of laziness and inertia (tired of rebinding everything, as you do). I tried to use the mouse w/ my left hand and couldn't. Too much of the controls are right-hand centric. Keyboard shortcuts for browsing are all on the left side, etc. It does feel nicer to have it on the left hand sometimes.