I posted on your other thread too. Pushing all the way down is not a big deal if the car is under 50k miles. But after that (roughly; on the original master cylinder) pushing the pedal all the way down can run the seal over built up gunk in it. This is because the pistons rarely go past the halfway-ish mark in a master cylinder under normal braking. My guess for why your brakes were dragging is in my other post too if you'd like to check it out. : )

 

Lol I think your absolutely right about this as I can't think of any other reason as to why it was dragging. At first I had thought it was air in the lines that got hot and expand to push pistons out but that seems over stretched a bit.