[gwc]

His point makes a lot more sense in the context it was originally intended. He's not making a point about programming or debugging in general; he's specifically discussing tech support as a one-man indie game shop. In particular, it's all about the cost-benefit tradeoff. In his words (taken from the first post in the series - http://jeff-vogel.blogspot.com/2011/06/seven-tips-for-giving...):

But at the same time, as a small developer, you have very little time to spare for support. Time spent getting the game working for one person is time not spent making a new game for everyone. You will need to develop a sense of when the time lost helping a person is not worth it, either because you won't be able to solve their problem or because they will not able to implement the fix you provide.

...

Remember: It's only worth the time to do tech support if you have the chance to, in a reasonable amount of time, fix a problem and make a loyal customer. If you realize that, at the end of the road, you aren't going to end with a happy person and a working product, end the conversation as quickly and pleasantly as possible.

In that context, I think his approach is very rational. If you pushed him, he'd probably agree that more often than not the issue is in his code (even if it's just a question of inadequate error handling). However, if the problem is only seen by a single user and will be a significant investment to try and fix, then it's simply not worth the time when he could be working on a new game, a port, or even a different problem that has been seen by multiple users.