Deals rarely look as good on paper as they do in a chief executive’s head. Comcast’s $31 billion offer for UK satellite broadcaster Sky just about passes financial muster. Investors expecting a higher bid from Rupert Murdoch’s Twenty-First Century Fox , with backing from Walt Disney boss Bob Iger, are betting on the triumph of sentiment over spreadsheet. The cable giant run by Brian Roberts on Wednesday firmed up its offer of 12.50 pounds per Sky share, beating Murdoch’s December 2016 bid by 16 percent. The move endangers the mogul’s plan to sell Fox – including Sky – to Disney for $52.4 billion in