Been running pretty cold on my tables, this table is super loose as usual.

I limp with in EP and everyone at the table sees the flop (I would guass average vpip is 70-80%).

Flop:
It is checked around.

Turn
Checked to MP who bets 4 into the 10 pot. He gets 5 callers so I call as well with my... I dunno, 3:d nut flush draw, gutshot and low pair I guess.

River
Checked to a shorty who goes all-in for 11, everyone folds to UTG who flat calls. I raise to 30.

Stupid? Brilliant?

I think it depends a little here. Since you have the second nuts, you at least have one of them beat, and for two other players to have the flush is at least unusual.

I feel like UTG can have almost any flush here--maybe nut (no need to raise it), maybe not. I'd probably call or fold more often than not here, but I don't think the raise is bad if you feel like you have a lot of call equity from inferior UTG holdings--and if you're pretty sure he won't re-raise you without the nuts.

UTG can NOT have me beaten, but shorty almost certainly has the nuts. If I call I am just giving away 11 most of the time, but I don't think UTG can fold so if I raise to 30 I will make 19 instead of losing 11.

Of course there is a tiny chance that my hand is good for the whole pot or that UTG flat called with the nuts and will re-raise me, but I consider it extremely unlikely.

Of course *I* wouldn't call if I were him, but *I* am not playing 70-80% of my hands and calling too much. I don't think he thinks his hand is good, I think he thinks he is beaten but is calling anyway because "There's so much money in the pot", "He might be bluffing", "It's only 19 more", "I'm committed", "He could have a lower flush/straight/set" etc etc.

I don't see how you get 8 as a profit though, I raise to 30, 11 of it go to the main pot (which I will lose) and 19 is what I put in the side pot. My profit will be 19.