"Preventing RSI" isn't the reasoning behind where to put Ctrl, though. People don't like it in the corner because it's (much) faster and less error-prone to put it next to A. Moving your whole arm is going in entirely the wrong direction.
FWIW: if you are RSI prone, you to be minimizing time spent on a keyboard in the first place, and heavy editor use is probably just a bad idea in general.