I think I went in for the first time after about two years. I made the mistake of attending a Gathering as a spectator about a month into my formal FMA training. I was shocked and appalled at the lack of clean deflection to checking to snake/vine disarms!
(The tongue face to indicate my naivete)
A few years after that, after being a troll on the boards and on the DBMA site, I ended up watching the clip on this site entitled "Rumbling Ruminations". I attended a DLO seminar shortly after that and I believe my first Gathering was a few months after that. I did not have any DBMA training, nor did I (unwisely) pursue any of the DBMA materials until about two Gatherings in. It's been 27 stick fights now, and I consider DBMA to be one of the most important elements of my training matrix.
So tankdriver, I'll give my usual recruitment spiel: anyone out there who has ever considered participating should be out there doing so. There truly is a "higher consciousness" that exists just above the world of drilling, sparring, and your day job. It's right there for all those who want it.