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.
Only person AFAIK to land exactly on 200,000/200,000 gs, WITH exactly 200 games played, with 100% completion including all DLC. 11-13-11. 200th game: Brink. Final achieve: Ark King.
Most recent milestone: landed exactly on 10,000/10,000 achievements won with 100% completion including all DLC. 3-29-13. Final achieve: Aperture Science in The Orange Box.
100% completion on every game played, no hacks, gamesaving, or mods. Legit completion is the ONLY completion worth aiming for.