I see your point. The problem is that friendly matches are not really good for testing. Private League testing would definitely give Supporters an advantage against non-Supporter managers.
But I bet that if they have released these tactics, they must have fully tested it because they have all the tools to simulate any possible situation in their computers.
In this case we just need to have "patience" and "take it easy"... ;-)
¡Me aburro! (Homer Simpson)