Not really sure on this. It does mean on match days there will be 2 centre backs not needed and will be picking up a wage doing nothing. Don't really think you need 5 centre backs to be honest..Unless PB is thinking about playing 5 in defence again? But oh well, would now love to see a centre mid, winger and a striker but highly doubt any of this will happen.
Your 2 spare centre back's comment makes no sense to me. the LB's and RB's can push up to assist, and we all know Adam pushes forward for corners or free-kicks etc. White is not bad also for getting forward in a counter attack.