Efficiency rating on nba.com?

["Hsu" <hsu@xxxxxxxxxxxxx>]

I didn't notice until recently that each player summary on nba.com has an 
"efficiency" stat.

The description of the stat is at 
http://www.nba.com/statistics/efficiency.html
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Efficiency: The Daily Recap
How do many NBA coaches quickly evaluate a player's game performance? They 
check his efficiency.

NBA.com now evaluates all players based on the efficiency formula, the 
same one also used by fantasy game players in Virtual GM: ((Points + 
Rebounds + Assists + Steals + Blocks) - ((Field Goals Att. - Field Goals 
Made) + (Free Throws Att. - Free Throws Made) + Turnovers)). 
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This formula seems rather arbitrary, but the description (and the fact 
it's used by NBA's official website) seems to imply that NBA coaches might 
actually use it.  What do people think about this formula vs. something 
like TPR?

Francis