Directionally speaking. Twisting a turret on top left or right to adjust for impacts that are left or right makes more sense in my head. Same can be said about vertical adjustments. Spin the dial forward to go up, rotate back to go down.
I already use my left hand for re/loading a mag. Assuming the rifle is on a bench, ground, barricade, tripod, etc. Why can't your left hand adjust for elevation if the dial was put on the left? Then put the parralax/illumination on the right?
I can understand on a long heavy PRS rifle why you would not want to do this if the rifle is unsupported. Holding it by the pistol grip instead of the fore end would just be, well, you would look stupid trying to do it. I guess sticking the buttstock under your armpit would help balance.