Cab for Hire: Dispatches and the Moral Collapse of the Political Class

I am still reeling from Antony Barnett’s Dispatches investigation into MPs and lobbying. Truly brilliant TV. Horribly watchable. Exquisitely awful. I watched half of it from behind my hands. This was Curb Your Enthusiasm meets the Office: political Dr Who for grown-ups.
Why is it always the Blairites who get themselves into these messes? Is it simply because they bought the New Labour compact with the market more fully than the rest of the party? Or is that they waded so far into unfamiliar territory that they lost their moral compass? None of this completely explains what is going on here. 
There was something rather sad about watching Stephen Byers wade so deep into a sewer of his own making. In the post-Blair world he seems utterly without direction. There was a time when he was the coming man and watching him boast about his monthly meetings with Tony Blair was just toe-curling.