ARLINGTON, Texas — AT&T Stadium is halfway through its life expectancy. Opened in May of 2009, the city of Arlington and the Dallas Cowboys’ efforts has “worked,” save for one minor, mystifying disappointment. The city/stadium has hosted but one Super Bowl, and there are no signs another is coming any time soon. Because everything is made to be thrown away, “new” stadiums only last about 30 years these days. At this point, we might want to just entertain the notion that one Super Bowl is all AT&T Stadium will ever host. At least one man refuses to entertain that “notion.” It’s probably closer …