Jayne’s book probably requires a university undergraduate-level familiarity with probability theory to fully appreciate.
I’d say that for the time being you don’t need to worry about bayesianism vs. frequentism. Just learn the basics of probability theory and learn how to solve problems.
Indeed, and I am sad to say that I have seen this even in the top-level posts and blog as well. I’m actually doing a write-up about evo-psych and why a rationalist community should maybe try to avoid it. I might post it to this forum if there’s interest.