Think we have done a lot to help Llorente get to the WC in terms of consistent game time. Although the 3-5-2 we deploy clearly isn't a formation that's suited to his characteristics, we also can't afford to field a formation to suit him. The last time we did that and changed to a 4-3-1-2 to accommodate Diego, we all know how badly that season went.
The players should adapt to fit the system and not the other way round in my opinion unless they are one of the very few players who can carry a team on their own.