I'd also say that the argument that you don't need multiple teams in one world because you could just join another world is a bad one. One a day worlds can be very slow. I'm only in two of them, mainly because one was the first one I was ever in, and Wooden because I wanted a new challenge. Even in Wooden, I realize its going to take me probably 6 months real time to field a competitive S16 team.
I'd much rather play in a 2 a day world and do it in half the time. Or maybe I want to get to D1 fast. But in a one a day world, that will take me a long time, real time. If these were all the same types of worlds, then I could see this argument working. But you aren't comparing apples to apples here. I'm currently in D1 Tark, and don't want to move from my cush MSU job, but I've also considered dropping down to take on the challenge of D2, because it's very competitive there as well with the GLV conference and others. I have never been in Allen world for example, and have no interest in a one a day world where I don't know the first thing about who's in it, and would take me forever to get anywhere, etc.
Under people's argument here, I can't get a second ID to take on the D2 Tark challenge, because the minute I make the ID, i'm now a cheater because multiple ID's = automatic cheater. That's a false equation. There are legitimate reasons to not allow multiple ID's that I agree with. But lets not muddy up the water with false equations, non sequitur arguments and the rest.