He prob had the guide made before the game even came out. I know I've had mine in a word doc 99% complete since last week since all the achievements are self-explanatory except for the chapter-specific ones and a couple Spartan Ops ones. I just was waiting till midnight MY time to put mine back up since it got taken down and add in all the youtube vids and the last couple descriptions, but seeing as this one is just fine there's no reason to have two on x360a. I'll stick with my walkthrough on TA. Good work OP.
400,000gs reached 1-13-15. Used D4 to get it (get it, it has 4 in the name) due to my disgust with how Halo: MCC has been handled. Achievement used for 400k milestone: Business as Usual.