A pyro warning. The Boston Herald's Tom Mashberg has a terrific story today on Paul Vanner, the sound man at the Station, who says he warned co-owner Michael Derderian months ago about the pyrotechnics being set off at his club. But it's hard to know where this information fits into the investigation, since Mashberg also reports that Vanner says Derderian appeared to take his warning seriously, and stopped booking bands that use pyro. A fascinating tidbit, but we're still a long way from knowing the truth.