(If PJ Eby's hypothesis of "naturally struggling"/"naturally motivated" mindsets is correct,

See Dweck's research on growth vs. fixed mindsets, and Seligman on optimism vs. pessimism. There are definitely some dichotomies of this sort out there in reality, and in the better self-help literature ("better" as measured by, "I got better results from it") tend to group personality characteristics in similar ways: generally speaking, nobody confuses success characteristics and failure ones.

then those would be the naturally struggling people, while the naturally motivated people can benefit to some degree from almost any self-help book, which may contribute further to them getting more praise than they've earned.)

Naturally motivated people are actually more likely to write a positive review, but yes, people who are struggling can definitely get into a religious zeal about books that they have only read, but not applied. I used to do this myself all the time, and I frequently see it in the emails I get about my own writing.

It seems that this is just the response to feeling validated, justified, and to some extent forgiven for one's past misdeeds: the new book or tape or whatever has presented you with new information that you didn't have before... therefore, you couldn't possibly have been expected to achieve anything, and it's not your fault. What's more, you now have hope for the future as well, and that feels good.

What I'm actually wondering about is whether there's a way to harness this response for good. Like, if I could offer a program where you only get new stuff once you've actually learned some of the old stuff. Mechanically, that's not difficult to accomplish, but developing and sequencing the material is another thing altogether. (Really, sequencing is one of my biggest challenges these days.)