To start with, tanking has nothing to do with the ability to win. Managers have to learn how to build a squad with certain speciality and versatility to handle matches with opponent of 20%- (outscore for goal difference) and and opponents of up to 20%+ (defend and counter for at least a draw). League draw will always involve teams within this quality range, and ability to win aggregate via goals scored in cup draws is even more important.

If we want to win consistently, we must be able to learn on how to train players to excel on the desired 1-3 white skills, and the few key players of 140%+ must have at least skills of 250%+, if not close to 300% around age 22 when joining as 18yo.

Try working out some white-averaging power training sequence to have certain attributes to those high %. Average players would not cut it in tough draws.