Im not sure what it is, I think the name MAY have something to do w/ it, Im really starting not to care. I was never threatend by DIR and embrassed it, but maybe because I only had about 60 dives when I first learned of it, and because I heard of it at my LDS by a DIR diver instead of on-line (namely SB).
People say, Ive done X # of dives and havent had any problems or someother lame excuse, thats fine. I dont care, I will dive w/ them. BUT I wont do any dive w/ them and even on easy dives its alot more enjoyable to dive w/ a DIR minded buddy.
If simple letters, or words keep you from learning something usefull, something that can make you safer, the do away w/ them. Call it what evern you want, but its a good system and deserves a look at.