No-one seems to have addressed the question as to why Vettel would want to go to Ferrari - it's not exactly the bee's knees at the moment (although getting better). Whereas RB is still cutting the mustard, although not quite as decisively as last season.
I absolutely agree Jen. If we are looking at a drivers choices when they consider the competitive nature of teams above all else, then of course, they should want to be at RBR, or where ever Newey is.
Saying this, I imagine that Vettel has always wanted to drive for Ferrari. Also he probably thinks the reason he has won two championships is as much down to him than the team. This is not trying to slander the man, I am sure all of the best drivers believe this.
If this is his opinion, then moving to Ferrari would seem like less of an illogical decision.
This could all of course be here say, if not however, i imagine the above comments have some truth