I don't think there's any chance of moving to a back 3, Cook is set on his system and to be honest i think it's a very good system that doesn't need changing - just needs to settle at this level.
I've seen James in about 4 or 5 games now and i think he looks very solid at the back but i don't get the impression he's got that natural inkling to bomb forward in the way we need our full backs to wing backs. I'm not been convinced with his delivery to be honest so far, he's put in a couple of decent balls but he's kicked a fair few of his crosses straight out of play thus far. It's not writing the lad off in anyway or saying he's been poor at RB, he's been absolutely fine but i just look at him and everything he does and i get a striking impression he will end up a centre back rather than be a right back as his career goes forward. With Byrne being our POTY and the type of RB that makes our system tick and our problems at central defence i can just see both getting in the starting line up and one of the CB's drop out as the season goes on. Probably not for a little while yet as Byrne gets back to full fitness and we give Dunks and Kipre the chance to adapt - but i wouldn't rule out James being Big Dans replacement and we haven't realised it yet.
Maybe i'm wrong but James reminds me of when Bale first popped onto the scene as a left back at Southampton and while he did well in the position he was fielded looking at his natural attributes it seemed likely he would end playing in a different position than where he started.
