So I have to think the root cause of this problem as the disc brake pads freezing to the rotor, and needing to be hammered on to free up.
But I don't know why the parking brake was dragging afterwards...? I blamed the cables at the time but after working on it today they seem to be just fine.
Bang my head over my sheer stupidity.
After driving for a few days sans parking brake, I decided to see what was up, as it was bothering me. I used chocks on the wheels, jacked up and cribbed the car so I could adjust the brakes. Perfectly safe. Adjust the adjusters, everything seems fine. Sets ok, no drag when off. I swear it's got an exhaust leak so I started and let it run so I could get under and look. Then shut down and because I've been driving autos the last few years I forgot to put into gear (manual trans)... and of course, my mindset is still "the parking brake is bad"... Jacked down, removed the last chock... and down the driveway it went. Thankfully I have a large rock in my driveway. But now I don't have a radiator.
Or a bumper. Driver's door is tweaked too, it was open when it hit the rock (tried to jump in, failed), radiator core supports are tweaked, I'm sure the list goes on.
I've been thinking lately that I shouldn't work on my cars anymore, I think after paying out from this one I might just be done.