If I knew what brand of whiskey he [General Grant] drinks,
I would send a barrel or so to some other generals.
-Abraham Lincoln
Source:Remark at Cabinet meeting, 1864
The gulf in productivity between average, good, and great programmers is so vast that a good leader is wise to make great exception to the idiosyncracies of those at the top, even when those quirks could be called character flaws.
Unfortunately, those who lack talent have often survived through mere superficial imitation. In Lincoln's day, lackluster generals with flawless pantomimes of inspired military prowess resented Grant for being the genuine article. I believe Lincoln was being facetious by suggesting that they were such good imitators that they ought to imitate his drinking, too.
So your best programmer wears hawaiian t-shirts and is surly with HR. Now all the mediocre programmers are doing it too, carefully cultivating an air of eccentric genius. CPound would be well within his rights to put the smack down on the preening ameteurs and tell them to crack open a couple books or win coding contests if they want to look good. But the star programmer, he's your General Grant, and he can fight bush-twins-drunk in his pajamas if that'll win the war.