Every band (particularly heavy bands) should take note of how Neurosis puts it down live. Come out, melt your face , finish and leave. It's the reason I have always loved this band live. None of that "this song is about" or any mumbo jumbo talk either. Kick ass and don't ask for any names afterwards! They even killed it w/o any visual accompaniment the last time I saw them. I was skeptical about it at first but they showed me that they can slay a crowd just by playing straight up as well.
It works for certain types of music...but also..that's an institution of a band. The people go there knowing what to expect and anticipate what they do. Its not quite so easy to pull that off with a room full of people who don't know who you are. But you're right for sure.