If I had to give an analogy.
Have you ever been in a position where someone rattled off a task list to you or instructions and you only caught a small piece of it? Then you have to ask them to repeat themselves or go more slowly or worse you nod and pretend you got the instructions but didn’t (this is me, I’ve done this)
Same deal with the subs I think. A lot of that info is flying right over your head and then you have to doubleback which makes more work just trying to parse the instructions vs actually carrying them out. Better to build a small foundation of internal understanding of HOW to execute the sub and build off that. Cuz really these are new ideas, beliefs, mindsets, it makes a lot of sense why we won’t grasp it the first time around or second and even moreso why it’s different for everyone. Some people have that foundational knowledge or intuitive understanding to build off the sub and others don’t and have to construct it first.