We heard George Parker earlier suggesting that the coalition has moved far more quickly into an antagonistic stage than its leaders had anticipated.
Messrs Cameron and Clegg insist their government partnership will continue until 2015 when they will fight a conventional general election.
But at what stage in advance of that election should they part company and start setting themselves up as distinct political parties?
The historian and politics lecturer, Dr Alun Wyburn Powell, has studied in depth the progress of Liberals in past coalitions.
He told me that the coalition of 1945 ended about two months before the subsequent general election.
I asked him if he thought there should be a similar gap towards the end of this coalition in 2015?