"How the contract with Thomas Cook would affect the taxpayer..." Simples, 3eng, it brings in a load of money to the treasury for an expensive asset during for periods in which it isn't being used.
"Thomas Cook pilots wouldn't touch it with a barge pole...?" You've asked them all have you, beagle? BALPA have a thoroughly sensible policy of discouraging pilots from volunteering to do extra services for nowt. Nothing to do wth rights and wrongs of PFI, just plain common sense. It's very likely they'll get the numbers needed, just not for nothing!