I play as Assault most of the time but I rarely use the noob tube, and I never use in close-quarters combat. Mostly I use it to take out vehicles or hit someone around a corner or something. IMO the main function of the noob tube is to take out light vehicles, groups of enemies, and enemies in hard-to-reach places. When it's used like that, it's not a noob weapon. I'm still always gonna call it the noob tube though
After a long while of offline play and playing one round online....n00btubing as I define it now is someone who fires more grenades in a round than bullets (which is reeeeeally hard to do playing normally, considering it takes 6-8 rounds from a normal weapon to kill