[Femto]

I see nothing wrong with it. You raise 45-55 UTG and you will probably get 2-3 callers. They hit their K/Q/J and you might get a little action. They hit better and you are going to find yourself in a difficult situation with stacks so deep. On the other hand if you limp it once in awhile, it is very likely the action will come back to you after a raise and you can 1) get more chips in preflop and 2) cut down on the number of your opponents.

L2+ I'd agree that it's -EV to limp AA UTG. But I'm fairly confident that it's not a bad move to use once in awhile at level 1--you'd be amazed at how many dorks will get all in with their AK/AQ when you reraise.