in reply to
The path to mastery
I completely agree... Just adding an example why tight code is not proper in every case.
Once I had to tune and slightly change algorithmic part of some data processing sw. Though I knew required new behaviour, I did not know definition or description of already implemented behaviour. And it was horrible journey with many many questions of type "Yes, I understand what it does, but if this and that is undefined, result should not be correct - is it mistake or is it wanted or it does not matter?"
Of course, missing documentation is the point, but more simpler, more primitive code could help me. Simpler variant of my speech could be "Yes, I understand what the code does, but why?"