Mike, I find it quite the opposite. My legs are able to handle a much higher load individually than I ever could in the back squat. Here is a link to me doing reactive single leg squats with 70 lbs of extra resistance.
https://www.youtube.com/watch?v=4K3aJy-5ppM
They're not quite pistols, but they're pretty dang close. I can get 5-6 normal reps with BW + 90 lbs.