Robert Peston wrote this in the Guardian yesterday:

True to its counter-intuitive form, this government has eschewed a progressive remedy: a flat £30,000 tax is by definition regressive, hurting those at the bottom of the income scale and an irrelevance to the billionaires. Surely Gordon Brown would not view his Britain as a land fit only for plutocrats - and not for foreign-born software engineers and Chinese language teachers?

He's right to raise the question.

But he shouldn't expect a reasonable answer. James Purnell (a minister, no less) has called Labour an ideology free zone. And as Polly Toynbee put it on Friday:

First mistake, Gordon Brown appoints a rabid Tory to be a minister - yes a minister - in the government without even joining the party. Digby Jones has proved to be as damaging an enemy within as the old Militant Tendency.

In this scenario logical policy is a random event.