Thanks, Nik
I've noticed that many players ask for specific tactics for some formation, while in my opinion one formation can have various tactic setups. Setup varies from formation itself, your team's strenghts and weakness and even more important, from opponents quallity, formation etc.
I agree with your statement that we shouldn't change too much times during the game unless we need it.
I've learned that when players are bad during the match, tactical changes could take low effect on match stats, but usually there was no turnovers in match. However, when players form is good, team is eager to react on changes and it could change match outcome.

Form gives effectivity and importance to tactics while tactics can improve or impair form. It can't be separated.

TE is sometimes hard to understand, and as in real life football, we can't predict match outcome, we can only guess. But there are some things that we can understand, adjust and do what is possible to do, what is in our might, to increase chances for good result.
Football, both real and virtual, would be boring if everything was predictable.