to be honest, does it really make any difference whatsoever?
I wonder if it reflects not just where you position the players on the grid, but the roles you assign and the players you use. Mine showed my favourite formation as 4-4-1-1 for ages, which I'd never used - I always used 4-2-3-1. But both roles were set as 'wingers' and my preferred AML was more of a winger than a forward, so if the game thinks it was more of a 4-4-1-1 rather than a 4-2-3-1 then I couldn't really disagree.
Or it could just be broken.