Maybe there’s a limit to schadenfreude, even towards a long-time rival. As the Mavs wilt in the twilight years of their franchise cornerstone, a Spurs fan may start to brush aside bitter memories of Jason Terry striking Michael Finley below the belt; of Dirk Nowitzki’s back-breaking and-one in 2006; of Juwan Howard and Derek Anderson in 2001; of Zaza Pachulia’s previous improprieties wearing blue and white; of an owner’s repeated jabs at a city’s noble artery. Maybe after watching their team take 18 of the last 21 regular-season meetings, after seeing their adversaries stumble towards the bottom of the NBA standings, people like me could try not teasing their old Dallas friends after each win and show a little friggin’ humility.