Depends on your squat form. If you're low-bar with a lot of lean (long femurs or something), you'll engage your hamstrings more than an ATG high-bar. Still won't contribute anywhere near what your quads are doing though.
The mythology behind season 1 was another part of what made it so good. Of course it also spawned dipshit theories like "Marty is the Yellow King, hurrdurr."