Another obsession is with numbers. Every sports addict lives with a head full of statistics, cross-filed for ready access, and many a baseball fan who flunked simple arithmetic in school can perform prodigies of instant calculation in the ballpark. Still, some statistics are more important than others. If a pitcher wins his 20th game, if a golfer shoots a 61, if a runner runs the mile in 3:48, please mention it. But don’t get carried away: