Bob Bailey, my mentor, was originally anti-DIR -- in fact, he has a SB post which states that in no uncertain terms. Then he kind of came around to the idea that Fundies was reasonable, and took it . . . twice. He now says he's not DIR, and he does heinous things like putting his backup light in a pocket. But when it comes to good skills, good planning, and team diving, he's mainstream.
We had a thread here a while back about what makes a DIR diver, and even those of us who are trying couldn't define the term. Until you're heading six kilometers back in a cave, the tiny details aren't in it; the basic gear configuration, the work on good skills and sharp emergency procedures, and above all, the deep commitment to team diving and polished situational awareness, are what I've picked up as the core of DIR (and I'm a fledgling, so I could have the picture all wrong).