Mate, here's how the game works: the lower reputation of the league that you play the easier to overachieve in it.
It took me only about a month after FM16 was released to make a tactic that allowed me to win any low reputation league with almost the weakest team in that league and if my target was winning low reputation leagues then I could stop to make tactics anymore long time ago.
When I say "low reputations league" I mean such leagues as Sky Bet Championship and any league below that league or any low division in Spain, Germany, Italy and so on, also, any leagues such Portugal, Turkish, Greece, Ukraine, Russia and so on...
The thing is that let's say with some tactic I was able to win Sky Bet Champion, Russian League or Turkish league with the weakest team in the league but when I used the same tactic in such high reputation leagues as English Premier League, Liga BBVA, Bundesliga, Seria A and some other then I even wasn't able to win these leagues with some mid table teams even after 4 seasons.
All that time since FM16 was released I have been making and improving tactics that would allow you to greatly overachieve in the high reputation leagues such as English Premier League, Liga BBVA or Champions League becasue as I said I was able to win any low reputation leagues with a tactic that 3 times worse than Sunfire already long time ago.
The difference in difficulty between any low reputation league and top 4 leagues: English Premier League, Liga BBVA, Bundesliga and Seria A is colossal.
And I'd say that anyone who tests his tactics in the lower leagues just waste his time because it's like testing on "easy mode" difficulty and if you really want to know how good is your tactic then you need to test it in the most difficult competitions in the game such as English Premier League or Liga BBVA.
So you should be ready that the higher you go the harder it will be to play and overachieve.
If someone never played in English Premier League or Liga BBVA with the weakest team then he has no idea how difficult this game could be
and when someone at first time steps into these leagues with the weakest team he gets shocked about how difficult this game could be.
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