Our first trip to Snow’s BBQ in 2009 was a life-changing event for a group of friends. If a milestone occurs and no one notices, is it still a milestone? That question certainly doesn’t rank with the great philosophical barbecue debates — i.e., foil or butcher paper? — but it is something we’re pondering this week. Why? This is the 400th published post since we launched the Texas BBQ Posse blog in March of 2010, six and one-half years ago. The initial post in our Barbecue Chronicles is still one of my favorites. It was about our first trip to…