Zach Mettenberger: I was just joking about J.J. Watt

July is a dead period on the NFL calendar until training camps start, which leaves those who keep an eye on the league to talk about things that would be ignored in a busier period. Things like Titans quarterback Zach Mettenberger responding to Texans defensive end J.J. Watt’s opinion that Mettenberger’s habit of taking pre-game…