Last night, Brian Williams did another thing that firefighting blogs might chide a former volunteer firefighter like himself for doing: he concocted a fake alarm to interrupt Jon Stewart during a clip reviewing Williams unflappable on air alarm moment on Tuesday. In anticipation of the staged cameo, the Daily Show host had been feigning mock indignation that the NBC newscast would be derailed by an in-studio fire alarm that wasn't able to be switched off fast enough.  "Williams," he lectured,  "You will deliver concise summaries of the day's events in a slick, digestible, yet blandly produced package, much like Lunchables, and you will do it every day of every year ever." And, a few lines later, the NBC anchor arrived with his own backstage "alarm." Williams didn't say much about his own incident, but delivered a serviceable "Not so funny, is it, funnyman?" retort before backing out out of the room while mimicking truck slowly going in reverse.