Funny, socially acute and deceptively gentle, these are part of the many sides of Bennett's humour that the British public loves, not least the Daily Telegraph readers whom he claims to despise so much, but who appreciate his sensibility so well. All the same, nothing can remove from the centre of the play the problem that both Auden and Bennett identified: that the lives of artists are often very much less "nice" than their work. Whatever one may think of Auden and Britten as artists, as people they were both distinctly unpleasant. Their lives were far from admirable. 

That can be made funny and outrageous. But one of the central themes of Bennett's play within a play — Britten's anguished obsession with very young boys and the way he dropped those who ceased to interest him — is not something that can be transformed into one-liners. That somehow sanitises it. Charming jokes between and about gay men are funny and touching. Joking about the age of desirable boys makes me feel uneasy. This obsession informed Britten's work, as The Habit of Art makes clear, but I am not sure this is the place or the way to consider such a difficult subject. It is tempting to agree with the line Bennett himself gives to Auden, complaining that artists should not be interviewed. Their private lives should be of no concern to anyone except those close to them: "The rest is impertinence." Bennett surely cannot mean that himself — impertinence is the stuff of art. All the same, there is something troublingly impertinent about the treatment of latent paedophilia in this play. 

The painter Edgar Degas was also far from a "nice" person. The problem with Timberlake Wertenbaker's The Line is that he seems far from interesting as well, which both in life and in theatre is almost worse. I found myself wondering why the author had chosen to write about him at all, if she did not find, or could not make, him more worthy of attention. He is presented as a dull bully, who does and says little of much note. His lines are sententious and wordy and even Henry Goodman cannot rescue them. The way that Degas took sides against the Jewish officer Captain Alfred Dreyfus in the anti-Semitic scandal of late 19th-century France could have been turned into powerful theatre, but in this production it has little resonance. Timberlake Wertenbaker even manages to make Degas' young protégée Suzanne Valadon somewhat boring, though in fact Valadon's life was sensationally interesting: outstandingly gifted woman painter, circus girl, small-time prostitute, lover of some of the most talented men of the era, single mother and temporary member of the haute bourgeoisie, she ought to have been a gift to a writer. 

In Degas' case, at least on the showing of this play, Auden was right. Degas' art is the thing. His life is residue, especially as he was so determined, with his extreme self-discipline, to sacrifice it to his art. It may not be impertinent to try to turn it into theatrical biography, but it does seem rather unnecessary. Anything that Bennett writes, however, no matter how nasty or dull the subject matter, can never be unnecessary.