[Assigning categories to coaches question]

I'm playing FM21. The game shows that the training category has the star rating of the most high-rated coach in it. Which led me to believe that I can have one specialized coach for every category while the others can coach multiple categories with low star ratings. The later helps with workloads. This has been my assumption for quite some time but lately I've noticed that my training results are quite sub-par. Despite good leading coaches and good facilities, many tried training schedules.

So the question is: does anybody know how the game calculates the coaches impact on the training in a particular category? For example if I have lets say 1 leading coach with 4 stars, and 4 coaches with 1 star, can I say that the category is a 4-star training category? Or some sort of average rating will be used?

[FM19 Tactics by TFF]

Is there a way to get a 3CD + WBL + WBR working out of those tactics?

Also, can I download old versions somewhere?

I also heard that using 3FCs has been a cheat in FM for quite some time (because it is overloading defense, a combination of FCs and AMCs can be used for similar results). Could you comment on that?

Noob here. Will appreciate any feedback. Thanks.