This week's Ed-Tech Podcast from Steve Hargadon and Audrey Watters discusses Software Carpentry a bit around the 23:00 mark . In answer to Hargadon's point about home schooling, and whether the way people learning programming even fits the notion of class, we have a couple of answers. First, most of the people we're trying to help don't know enough (yet) to know what to type into Google, how to recognize when they've stumbled upon an answer to their problem, or what to tag a question with on Stack Overflow. Some can climb that hill themselves; a handful can't, but most won't (see below), so one of our goals is to help them get from A to B so that they can get from B to Z.
In addition, while the scientists and engineers we're trying to help might think that computing is interesting, their real passion is quantum chemistry, neurology, or climate change; in practical terms, computing is a tax they have to pay in order to do the research they actually want to do . From that perspective, "wander around and stumble upon" feels like a high-risk strategy, so they (mostly) vote with their feet and don't do it.
Second, even those who do wander and stumble tend to find very different things. As a result, there's no common core of skills or assumptions that one researcher can reasonably expect her peers to be familiar with. In contrast, most researchers can expect colleagues to know at least a few basic things about statistics, and to share some cultural values about when a correlation is significant and so on. In choosing what to include in our core, we're also (implicitly) making a statement about what that core is, and what's reasonable to expect others to share.
 What's really interesting, though, is the discussion in the first few minutes about Silicon Valley's ed-tech amnesia.
 Regarding Hargadon's comment about "willingness to hack", I think that every researcher I've ever met has that in spades—they're just investing that energy in something other than programming. And yes, lists of "things programmers need to know" make me yawn too—but only if I already know enough about the topic to forge ahead on my own. I'm really grateful for "must read" lists whenever I dive into a new area...