By and large, BABIP is based on luck when you're dealing with major league pitchers because their talent level is so high. Of course if you or I pitched we'd have a BABIP of .800 or more.
Naturally some pitchers have different BABIPs because of their profile (e.g. groundballers have higher BABIPs because ground balls are more likely to be hits than fly balls). But by and large, a BABIP of .311 for a single season is just not indicative of anything really. I mean the league average BABIP last year was .297. That's hardly a difference at all.
And it's a career .307 (mlb average during his career is .298) and he has only pitched 114 big league innings.