Though of course there are no rules, I think this demonstrates antipatterns for art (and life in general), and is meant to look like they know what they're doing to noobs watching the video: premature optimization and performative mechanical planning and measurement where you should just use your intuition bro

Get the gestalt down filling in the details of small features. If you start locking in high frequency details while the low frequency details are wrong, it's all for naught. And the low frequency features are determined in relation to each other, to the gestalt. The first few strokes you make are a seed for a fractal algorithm that the rest unfurls.

I don't have formal artistic training but I know this is also what they teach, maybe in different words