I agree, red arrows on offensive player and blue on defensive player causes counter-effect.
Btw. I've today played 4-DMC-2W-2AMC-ST against weaker 2DC-DL-DMC-4-2.
What I've noticed during the match:
I've started with red arrow on ML, but during the match decided to put red arrows on fullbacks. BP increased immediately for 2%. That's probably because opponent had 3 wingers (me 4) and because his wings are weaker than mine.