Does playing players way out of posistion decrease their stats? What happens to them when they get a red boot? Just get lazy and don't bother playing? I remember trying Ronny upfront but didn't like it. Prefer him on the left where he can cut in... and Messi has been a god for me. Really like him in 12, hated him in 11.
IF Soldado looking likely. Maybe IF Benzema and IF Soldado next week?
nobody knows for sure. but i have seen a few things which suggest chemistry does a lot more than what you think it does.
i think it drops their consistency, for example say if the player would normally make 9/10 passes, now he will make only 7/10 passes, etc. think it also effects morale (being on the bench used to effect morale, instead of in the starting 11, but i think they have changed it, but tbh nobody knows).
in my matches against kill, i felt my whole team were "slow", robhino, neymar, pato, johnson, etc all have a minimum of 86 pace, yet couldn't out run his slow bundesliga germans. now kill was using a full 11 chemistry team, every single link was a solid bright green one, whereas i only had 2 or 3 solid green links, compared to his 20 or whatever it was (each player has more than 1 link).
i then played a tourney game straight after and it was like night and day, my whole team ran a lot faster. so i can only guess it was his full 11 chemistry affected my team (making his team play better).
i think the same thing happens when someone uses a full bronze team with 100 chemistry against a gold, but the handicap is far greater for the bronze team, it automatically makes all of your players slower and also effects their consistency, making you unable to pass fast, etc. it's a lot worse than when playing against a full chemistry team.
EA will never release any details on what it does, so you really do need to see what happens within the engine when you play.
i have never used anyone with a red boot or a broken link, but i have also never played with a full chemistry team (secret 11 chemistry).
since you have all the players, make a full Barca team, all correct formation and position. then make another team with players from all different teams and nationality (e.g. dont link di maria and mascherano, link alonso and sanchez, instead) and one or two in the wrong position, and compare and see what happens. from what i know, your passing and shooting (consistency) will be off, the amount it is off depends on the chemistry and morale of the player.