Michael Gove's announcement  that university tuition fees will be capped at £9,000 – £2,000 higher than originally suggested by Vince Cable – spares us the unlimited market proposed by the Browne review .
But this still represents a significant increase from the current limit of £3,290 and Lib Dem backbenchers, all of whom (including, as shown, Nick Clegg) pledged to vote against  any rise in fees, are understandably concerned.
In what looks like a damage-limitation exercise by the coalition, Gove announced the increase on the Today programme this morning and David Willetts will make a Commons statement at 12.30pm. Cable, who is officially responsible for universities policy, is nowhere to be seen.
The coalition agreement allows the Lib Dems to abstain from any vote, but many, particularly those who represent university seats, are determined to honour their pledge.
The latest rebel is Jenny Willott, MP for Cardiff Central and PPS to Chris Huhne. She said: "I will not support an increase in tuition fees and I'm deeply concerned about increasing levels of student debt." Should she stick to her pledge to vote against any increase in fees, she will be required to resign or be sacked as a PPS.
Other rebels include the party grandees Ming Campbell and Charles Kennedy, Greg Mulholland, MP for Leeds North-West, Julian Huppert, MP for Cambridge, Stephen Williams, MP for Bristol West, and (of course) Bob Russell. In total, as many as 20 of the party's 37 backbenchers are expected to vote against the government.
The coalition isn't heading for a Commons defeat – that would require at least a dozen Tory MPs to join the rebellion – but it is facing the biggest rebellion of this parliament.
Lib Dem MPs should not be bought off by talk of the government "widening access". Nor should the argument that the "situation has changed" since May persuade anyone. The Budget deficit was larger, not smaller, at the time of the election. The Lib Dems have a moral duty to vote against higher tuition fees.