Aging Curves for Guards   Prior to further exploring my initial,
value of defense premise, I continue sidetracking into player
aging.  As noted in my last article, an exploration
of positional groupings will now commence.  Those are: Guards,
consisting of point guards and shooting guards (all positions as
per basketball-reference); Wings, comprising shooting guards and
small forwards; and Bigs, the contingent of power forwards and
centers.  Today, guards are the focus.  With the backcourt crew,
several previous trends continue, primarily offensive
performance peaking in the late-twenties, and appearance of a
minor swoon in the age 25 to 26 timeframe.  Position specific
outcomes also prove prevalent though.  Mainly, guards are
the League’s best players at bucket-getting, but they stink at
defense, generally not improving much at that end through their
careers.  Add it up, and as a whole, they are the NBA’s least
valuable group of players, rarely providing above average 2-year
APM (as a group, only at age 30 an