Yeah man, nothin' wrong cornering it. I smoke by myself, but I still corner all the time, I don't like to waste it just cause I have it. And on occasions I will torch it, and have lighten the thing on fire for a good 5 seconds (I was too busy hitting it to put it out) and I'm sure that wasted a few hits...makes it throw of smoke like a mofo!

If your friends don't mind though, and its not your weed, might as well torch it and waste their weed since they don't care.