every detail of the entire syllabus off the top of their head at any given moment. (PCNs and assumed weights of passengers on different types of flight etc...) Unless you are a true anorak.
Well you might think that but some very none anorak pilots do actually know there poo.
My example I use during training is ETOP's why do we mention it when we arn't qualified for it, there is no way in hell the aircraft will ever be approved for it etc etc.
We mention it because they need to know that we can't be more than 60mins single engine away from a divert. And that is not only for flying across the Atlantic. Now you might say so what, well regularly operators take turbo props directly across the bay of Biscay completely busting the 60min ETOPS requirements.
There are loads of little nuggets like that, if you bust facilitation rules you will go to jail and get a hefty fine.
So a lot of it is just to make sure you know it exists.
I agree something's are more of interest than other depending on the type of flying. ie I have dumpy large tyres and as lower PCN as you can get. The biz jet boys are looking at it all the time because they have skinny tyres.
I actually read that the OP is doing the right thing, he just wants some advice on how to mange his time. And good for him I say.
I wouldn't say forget about it after every gate, put the occasional revision period in to recap the previous stuff and just refresh what's been previously learnt.
Some subjects that you are familiar with you don't have to do it as much. My problem subjects were air law and ops procedures. The tech stuff some of it was the 4 th time I had covered it since I was 12 so to be honest I did the progress tests with only skim reading the sections. The air law stuff I had to go back to time and time again because it really didn't push my buttons. Some others are different and that sort of stuff they suck into their heads and they struggle with the tech subjects.
So everyone is different.