It's a speech which No.10 should welcome as it's a not altogether unsuccessful refinement of the blunt "Labour investment vs Tory cuts" line: setting it in a framework of "tax increases for those that can afford them", public service reform and waste-cutting. Sure, not stuff that meets the challenge of the debt crisis - but politically smarter than yet another dividing line from the Dear Leader. And that's why, in the end, I imagine it will be rejected by Brown and Balls. They'll regard Darling's more measured approach as a direct attack on their crass politics - and perhaps rightly so.
What we're seeing now is a defining split in the government, and one which could fester more openly than the Blair-Brown divide ever did. On one side, you've got Balls and Brown - who, you feel, are too far gone to back down from their crude dividing line now - and, on the other, an emboldened Chancellor whose rhetoric on "living within our means" somtimes chimes more closely with that of the Tories. Expect fireworks around the next Pre-Budget Report, if not sooner.