Absolutely, I'll take a shot at this great question.
A common trait of elite level pitchers is: They all get their front hip going forward to home plate early.
From some pictures, that can make them actually look like they are leaning back. In fact that is usually not true--the forward momentum of their front hip briefly leaves the rest of their body--the head, torso, and legs--behind. As the stride leg is coming down from its lift it does have to follow an arc-shaped path to catch up and pass the hips into stride.
I don't think many pitchers, if any, actually "kick out" their leg sideways and then bring it around. It is a smooth arc-shaped motion.