Confusion on the Dunning-Kruger Effect

Well said. You're right of course. He is entirely misreading the graph (and thus the effect itself). The positive correlation he correctly sees in the graph merely says that the self-perception of more competent people is higher than the self-perception of less competent people. This is not at all what he concludes from this correlation. He claims that "the bias is definitively not that incompetent people think they’re better than competent people", but this is simply wrong. The data shows that those in the bottom quartile rank themselves in the third quartile (above average). It's true that those in the second quartile ALSO rank themselves in the third quartile. Indeed, the remarkable thing is that all of the groups rank themselves between about the 57th percentile and the 74th percentile. That is, those who are below average (those in the lower two quartiles) think that they are above average, and those in the top quartile (on average) think of themselves as being somewhat weaker than they actually are.

I didn't even bother reading the rest of his post since he didn't even get the basic concept right .. as you pointed out with your "(almost)".

PS A tad annoying that you seem to no longer be using Disqus. (I'm rather unlikely to join another comment system.)