I'm still going to play some DP tonight, but that's way too many posts about one game, so just to fix that, I installed another.
Last time I played this, I had nearly 100%'d the game, and the only thing I hadn't done was beating Heroic mode. But I stopped, because I figured Heroic just going to be fucking impossible, or at least, I didn't want to attempt it. Insane difficulty was hard enough and, if I remember correctly, Heroic is supposed to be even harder while also disabling mid-level saves/checkpoints.
I wanted to try Heroic someday, but that won't be today because Heroic mode is locked. (The game doesn't use Steam Cloud, so my saves are gone... and yet it still remembers my profile details like total deaths, total kills, etc., so it's using some kind of Steam integration outside of Steam Cloud.) Well, I suppose I might as well torture myself by jumping straight into Insane difficulty despite not remember how to play the game, and if I can beat it then maybe I'll try Heroic after that. (Almost no chance though.)