I have read my OD&D books and Chainmail, cover-to-cover, so many times now that I can almost recite them. My study of them has been intense enough that it's yielded a pamphlet instructing the use of Chainmail combat with OD&D. It has yielded a supplement for play in Robert E. Howard's Hyborian Age. On the same page I host a pamphlet that another user did for Burroughs' Mars series.
Indeed, my study of these rules eventually led to me creating a game of my own, which explores what may have happened had the Chainmail Man-to-Man rules become the core root of D&D instead of the d20-based "alternate" system.
I have been involved in endless discussions and debates over at The Original Dungeons & Dragons message boards. I adore the original iteration of this game. I find it freeing in a way that no other RPG (save perhaps B/X D&D and its eminently faithful clone, Labyrinth Lord) since has matched.
Older edition (not just original, but 1e, 2e, B/X, Holmes, and BECMI/RC) D&D study has created an explosion of clone games, affectionately termed "Retro Clones" and an entire movement which has dubbed itself (for better or worse) the Old-School Renaissance. That this name has become the subject of some contention lately is moot; it's there and it's drawn some attention.
But I have come to the conclusion lately that we don't have much left to study about OD&D. Indeed, sites like Philotomy's Musings and Grognardia have said more than I ever could about this game and the use of it. What else is there to say that hasn't already been said? The game isn't that long, nor--despite some common complaints about it--is it that complex or arcane in presentation.
There are, of course, some arguments that linger. One poster over at the D&D message forums continues to insist that the Chainmail Fantasy Supplement was never intended for use with the mass combat rules, this insistence based entirely on a statement Gygax once made in an interview to that effect, and completely ignoring the constant references to the mass combat tables throughout the entire section, and the fact that Gygax changed his mind from interview to interview throughout his life. You can tell which side of that argument upon which I fall.
But these types of arguments are pointless to pursue, and don't contribute in any positive way to D&D study and (dare I say it without sounding pretentious?) scholarship.
This leaves me in a bit of a kerfuffle. What is there left to write? I miss digging into OD&D and pontificating on some aspect of the rules or other. But lately I feel like I'm just treading on already well-trodden ground. Like most OD&D fans, I don't find much of intense value in the supplements, save perhaps for the new spells and classes, monsters, variable weapon damage, all the stuff that later just became canon to AD&D anyway. And none of that really merits study. At least, I don't think it does. Maybe I'm wrong. Maybe that's where I need to head. Dig into those five (I include Swords & Spells) supplements and see if there's anything there to talk about.