Where is the discussion "between understanding and expertise"? I scrolled over the way too long text reading some chunks here and there but nothing sticked according to the title here. Is it even the right post?
"It’s not quite true that Feynman could not accept an idea until he had torn it apart. Rather, the idea could not yet be part of his way of thinking and looking at the world. Before an idea could contribute to that worldview, Feynman wanted to turn over the idea, to see why it was true, from any angle that he could find. In other words, he wanted to connect a new idea to what he already understood and thereby extend his understanding" (http://www.freakonomics.com/2011/04/08/how-richard-feynman-t...).
> Agencies don’t hire writers just because they know the rules of grammar. We hire them because they’re eloquent, lucid, imaginative wordsmiths. We hire them because of their practised ability to lovingly craft words into things that work. Things that make people feel.
EDIT: removed snark
The thing is, that knowing and understanding the features that discriminate experts from nonexperts doesn't help you much in your desire to become an expert. If you understand these features you can tell more accurately, if you are an expert yourself or not. At best this helps indirectly with telling you how much your learning task is achieved. At worst it just destroys your motivation. The question of how to become an expert is still open, though.