In my Portsmouth which play Championship tactic from OP bring to come down position. In League 2 and 1 bring me that tactic titles. I dont know what i am doing bad. I dont use OI,training Balanced/Attacking. Its strange that tactic works in lower league and in Championship is completely rubbish and concending a lot goal from cross in open play.
The leaky goals from crossing out wide is a case iv'e been trying to sort out since first asembling the original v0lliz-433, and i can stop it from happening but it comes at the cost of scoring a lot fewer goals so its really not worth it. Ive learned to live with it, im thinkering about increasing closing down for LB/RBso te opposition wingers have less time with the ball.. No easy solution to that problem..
Only answer i can give as to the reason it not working for you in the Championship, perhaps your team isen't good enough for your league, it originally designed for using fast players with technique to keep up with the high tempo. But some of you make it work in lower leagues and i suppose thats because your teams have sufficient skills for your league..

