You should look at Khris guide for all this and majority of veteran managers agree with this theory. In short there are a numbers of parameters according to which a result of a game is decided.

Some parameters like Team Quality and Formation are primary. They are always taken into account for a game simulation.

While other parameters like Condition, Morale, Win bonus etc are secondary. Among all these secondary parameters only a few are choose for game simulation. So condition will have zero effect on your result if it isn't choosen for a simulation even if you play with nil condition.

All we have in Top 11 are theories. Devs have never said a single things about how the game functions. So you will see difference of opinion on every topic.

The only thing we know for sure is that if you have a good quality team, you will end up winning majority of your matches.