I use it exactly for that, and it really helps me when navigating in Emacs (holding Ctrl with pedal is much easier than holding it with your pinky). Your experience may vary, of course.
I imagine that resulted in far less pinky-strain.
Knight keyboard: http://world.std.com/~jdostale/kbd/Knight1.jpeg
Later followed up with the space cadet keyboard: https://en.wikipedia.org/wiki/Space-cadet_keyboard which added super and hyper.