In my ten yrs of instructing (averaging 20 hrs per mth) I've found this to be true and VERY helpful to the student.
Before I give the lesson I like to find out my students background, and how they think and process life.
It dramatically helps me explain flaws I find, and clearly helps the student understand more quickly.
I've found, that change usually takes about 3 mths to incorporate and no longer think about it.
That's providing your playing more than once a week, otherwise your always seemingly/realistically ''starting over''.
When you correct a major flaw in your game, that change effects your whole package.
I normally find one/two things wrong with a players game, and only work on that the rest of the lesson.
I don't find it helpful to point out ten different things a player needs to improve, why?
It's toooooooooo much.
Yah gotta crawl before yah walk.
One or two things at a time are plenty to work on for the next three mths....and incorporate, so your no longer thinking about it.
bm