I was at the Electric Masada show in Vancouver, and there wasn't any audience confrontation at all. At one point some guy got up and started dancing and drumming on the stage, but Zorn didn't say a thing. I can't say i blame him for tearing into that guy, though Whether they're shouting praise or derision - it can really take you out of the moment or music, as it were. Case in point being the night after Electric Masada, i saw Diamanda Galas at the same venue, and there was a couple behind that just would not shut the fuck up - making inane comments and so-forth. It's happened before at other shows, but i never got so annoyed that i said anything - but this time it was so distracting i had to turn around and tell them to shut the fuck up, which thankfully, they did. There's probably more tactful ways of dealing with them, but interruptions are interruptions - regardless of intent.