Yes you can. My last three cars have had a volume knob under the left thumb. My current car has a second volume knob behind the gearstick, and the A/C is the only analog dial along the center console. I can easily adjust both without looking away.
I have volume controls and similar on my steering while, and I never use them.... because I can never remember which is where. I prefer my stereo controls to be in the stereo controls area, my climate controls to be in the climate control area, etc. Spreading them out makes it more annoying to deal with.
