Leatherhead
Possibly a Idiot.
Would that DMing for a group at that level or playing as a player at that level? Either one? One or the other?
I haven't played on the player's end yet. I have DMed levels 1-7 and now 11, as I just bumped my players up 4 levels (with an in-game reason for them reaching paragon - think Final Fantasy I class change quest).
In a month or so, I'll probably get to play my first level 1 character!
It may just be me, but I count DMing as playing the game. The controlling characters and rolling dice aspects makes a DM different than a simple referee.
Unless for some reason you are only acting as a official rules interpreter and someone else is playing the NPCs....