Nick Clegg put up a highly competent performance standing in at Prime Minister’s Questions. He deputised so well that there were moments when he seemed to forget that he is not a Conservative.

This was most noticeable when he accused the Labour MP, Lillian Greenwood, of “wilful scaremongering”, for raising doubts about the future of Kettering Hospital, echoing what David Cameron had said three weeks earlier. But Ms Greenwood had in her hand a leaked document compiled in July by NHS officials looking into ways to rationalise services across five hospitals in the East Midlands and Home Counties, who suggested that the “best option” would be to cut Kettering Hospital to less than a quarter of its present size, from 658 to 143 beds.

Kettering adjoins Corby, where there is a by-election next week caused by the resignation of the former Tory MP Louise Mensch, and where the Conservatives have every reason to fear that Labour will take the seat from them. Why Clegg should put his credibility at risk to help the Tories through a tricky by-election is a bit of a mystery.

M-factor in Lib Dems' next move

It has long been rumoured that Nick Clegg’s future is in Brussels, where the term of office of the UK’s current Commissioner, Baroness Ashton of Upholland, ends in 2014. As well as giving Clegg a secure job for which he would be highly qualified, a change of leader might improve the Liberal Democrats’ chances of avoiding a wipe-out at the general election. But it is not going to happen. When the anti-EU Tory rebel Mark Reckless teasingly raised the topic yesterday, Clegg’s response was unequivocal: “I will not be a candidate.” A party source said afterwards that the reason can be summarised in one word – “Miriam.” Clegg met his wife, Miriam Durantez, when they were both employed in Brussels. She, I am told, has no wish to go back.

Lib Dem love-in

One of the more waspish exchanges yesterday was between Clegg and the Labour MP Rosie Cooper, whom the Liberal Democrat leader caustically accused of having “packed every soundbite” into a question about flooding in her West Lancashire constituency. There is a hidden history there. On her website, Ms Cooper says that she entered politics at the age of 16 and was a Liverpool city councillor for 28 years. What she coyly leaves out, which is also omitted from her entry in Dod’s Parliamentary Companion, is that she was a Lib Dem all those years. She spent more years in that party than Clegg has. She was a Lib Dem parliamentary candidate in four elections, only to resurface as a Labour MP in 2005. Hence the edge to Clegg’s hostility.

In the Daldrydums

Stephen Daldry, who was executive producer for the Olympics opening and closing ceremonies, is not impressed by the impending decision to replace GCSEs with the English Baccalaureate. His beef is that the Education Secretary, Michael Gove, has decided to leave the arts out of the core curriculum, raising fears that state schools will stop teaching the arts. That is on top of the cuts in government funding, and the lecture that arts organisations received from the new Culture Secretary, Maria Miller, who told them that they will have to get better at asking for money from private sources.

“We’re back to where we were 15 years ago, where we are having to fight for old principles, fight for the old ideas and ideals of a country that should be at the forefront of what we expressed at the Olympics,” Daldry complained, during a ceremony at the National theatre in which he was handed the Peter Brook special achievement award. He was backed up by Ruth Mackenzie, the Cultural Olympiad director, who said that they had been “absolutely” reliant on the young being able to “develop their skill in schools and in subsidised theatre”.