It is... for example today i picked bolt nova ww (good for normal mode) and we are playing maybe 10-15 minutes in normal mode... i am winning and i am level 16 while other players level 10-12 and they make -UIM and of course i lose.
Its very interesting that SSD or ARS yu can put only before mass (not later) but UIM you can put whenever you want during whole game. Also you need only 5 players (less than 50% players in game) but for SSD or ARS you need more than 6 players.
I have 2 ideas about UIM
1) just delete whole stupid UIM mode
2) only red player (need 20 or more codes) is allowed votestart UIM mode. Need more than 6 players vote YES and you can make UIM mode only before mass.