This phenomenon is called survivorship bias, with the part about highly competitive careers being especially relevant. In particular, to correct Paul Graham on this:
As far as I can tell, the way they taught me to program in college was all wrong. You should figure out programs as you're writing them, just as writers and painters and architects do.
No, I would simply argue that true reason he can "sketch" almost entirely as he programs (i.e. figures out programs as he writes them) is that he is Paul Graham. In much the same way that you don't just start learning calculus at 12 and become Einstein. Apart from that, the rest of the answers provide some excellent advice on the overall advantages of mixing both the "plan-ahead" and "retrofit-as-you-go" methodologies.
There are "fail-safe" ways to increase productivity on average and this the actual purpose of formal education. Catering for talented individuals will always have a lower priority (though not too low, of course) than the general public, simply because there are too few. And talented individuals often think of themselves as nothing special. Well, usually, they're wrong. And, sometimes, their personal experience does not apply to everyone, not even the majority, especially when it contradicts what has been verified to work better on average. In a few words, you just cannot extrapolate from outliers.
When was the last time you tidied up your desk/room? If you are/were one of those people that "thrive in chaos", always programming among a holy mess of things unimaginably irrelevant to a desk... would you suggest that all these teachings about keeping rooms/desks neat and tidy were wrong?