It would be wise to approach this topic with some detachment, as if debating whether red or black ants have longer lifespans.

There is a risk of feeling one's self-image threatened by this thesis (and its opposite). That perception of threat often ends rational thought.

I think we all suspect that any correlation, positive or negative, between GPA and programmer "value" is merely aggregating several trends which may oppose each other.

Thus, there may be a current of brilliant, rebellious tinkerers who never get good grades but write good code; there may be a current of lazy underachievers who get bad grades and write bad code.

And people change with time. Someone who gets bad grades at 19 but writes great code at 29 may have changed into a "good grades" type.

I'm not sure we'd even agree on what a good programmer is. The truly bad is obvious, but one man's elegant virtuosity is another's unfixable nightmare.