That makes sense, a couple of years ago there was a lot of misleading interpretations going around, precise definitions help clear things up. I read Peak a while back, and I must’ve forgot that distinction.

I found the Klein book you mentioned more useful than Ericsson’s as well, that Fadde/Klein paper I mentioned was also pretty helpful. I need to reread both, and put them into practice more than I have. I read too much, and I don’t get the tacit knowledge that comes from experience...

Another good book is Surpassing Ourselves by Bereiter and Scardamalia. They studied how students developed writing skill. Their definition of expertise is a bit different than Ericsson’s, but I think it is more useful.