Lad let me give some insight for you.
Indeed the tactic was just tested on TFF's 75 Siblings and it tested quite poorly.
Am I discouraged from that?Not at all. And I would give you some examples why:
Have a look at my friend arnold tactic:
Hey there lads try this new tactic by my friend Arnold master fm tactician. He won the bundesliga with Mongladbach first season 90 pts. I don't know to many nuances with the training and such but he said that the right fullback takes the corners...
fm-base.co.uk
It was rated 2 stars on fm base testing.
It wasnt rated at all on TFF's Hot Tub because they require your own results nowdays if you want to test a tactic there (I don't have the time to test it).
He won the Bundelsliga with Borrusia Mongladbach first season. IF YOU TEST that tactic in simulation I can bet my kidney it won't fair so well.
Then he used the tactic with another team as you said (if you go from the notion that for instance his tactic works with only one team). Promoted first season from the championship. THEN IMMEDIATELY won premiership first season (middlesbrough). Then next season won champions league (his first champions league campaign with middlesbrough.) And I'm sure ANY club with even remotely suitable to his tactic he can repeat the success.
Regarding my specific system , it requires certain type of players that some clubs you tested simply dont have for instance I need 3 up FRONT with a Target man. Liverpool DO NOT HAVE any striker that can play a target man ( the only option even remotely suitable is divock origi but he would suck and he is not that great in the air).
Simular situation with psg altough psg is far more suitable and maybe situationally icardi can improvise as a targetman since he is ok in the air but he isn't very tall.
Bayern the only striker they have with any height is lewandowski and he would be a waste to play a target man ( bayern are suited for 1 up front systems).
That aside , simulation results and results in actual play differ so much that often times tactical "testing" goes out the window completely and due to the nature of this tactic this is a prime example of such a situation.
My advice if you are going to suit this tactic in simulation suit it with a team that has plently of strikers and a tall forward at minimum.
That being said I would try the tactic with other sides ofcourse and see the nature of it's consistency and performance but I am completely convinced this tactic is worthwhile.