I can’t remember the last time I saw a mosh pit at a show. And it’s not because I’m old or anything (although by punk standards I’m ancient), because I go to shows all the time. It must be the way things go in Boston because I’ve seen my fair share of “No Moshing” signs since moving to the city. I’ve almost begun to think they were a thing of past, until I saw Jeff Rosenstock at the Sinclair, because...