I think we should take it game by game. Bertrand did an excellent job against Newcastle to nullify Ben Arfa from the right and also added balance to the team. but when we face a weaker team, rdm will sacrifice him for a more attack minded player. it depends on the opposition. mata and hazard have shown they can combine very well without the need of a 3rd attacking player although a 3rd attacking player like oscar , marin or moses wouldn't hurt one bit when we are trying to break down a stoke city for eg