The OP is clearly smart enough to analyse what they read and will be able to pure out the knowledge they need eventually. Been there, done that, confusion and feeling overwhelmed and all. Got out the other end with a pretty clear idea of my interpretation of common sense dog training theory and techniques.
But in the end of course it isn't a theoretic science. You'll only really get it if you practice it. I think like lots of people I was reluctant to use treats for example. Until I experienced the whole process from start to finish and now I am a massive fan. Because it goes so way deeper than 'bribing' your dog into being 'good'. Using the clicker also taught me a lot. I rarely use it anymore now, but I don't think I would've "got it" as fast if I wouldn't have at the start. So it was a training tool for me more than for the dog!