I think it's like this: Six months to two years after starting a moderately-sized code base, you start to see why these things are important. You see that they're actually saying something fairly (though not totally) concrete. The more experience you have bumping into the issues, the more concrete the advice becomes.

But I can't give that to you in something that you can read in an hour, or even a day. I might be able to give it to you in something you could read in a month (of 8-hour days reading). It's really hard to show in a one-page example.