In this case, unfortunately it is partly right to finger DE&S. Although the "requirement / budget" envelope has been set elsewhere, DE&S have managed to get themselves to a position where one bid is broadly what they asked for, price-wise, but light capability-wise, whereas the other is capability heavy, but also reassuringly expensive, not least because of its build strategy. Lord alone knows what the Boxhead team came up with, but given the paucity of UK build yards outside the two Brit teams, they're probably knackered price-wise as well. There is probably a way through this, if only MoD had sufficient technical and commercial capability to assess such disparate bids. What a shame they completely managed to stuff up the advice-side contracts a year ago.
Oh - and those who would blame this on "the carriers", ought to have a good long look at where the budget lines are that are actually eating all the money. Not holding my breath they'll understand it though....