Nearly 40 years ago, when I began reviewing theatre, a first night was a first night. Now the 'first night', so called, can sometimes take place a month or more after the production opens. Its alternative name these days is a 'press night'.

That theatre managements often arrange for weeks of previews (and not always at cut-price) is not universally recognised. Writing in last Saturday's Daily Telegraph, restaurant critic Mark Palmer justified his immediate review of London's just-opened Mocotó by stating: "The bedding-in argument has always been spurious. Actors have to endure first-night judgements . . ."

The last-minute cancellation of Tuesday's press night for the RSC's high-profile King Lear, with Sir Ian McKellan, will have focused attention on what goes on, however. The reviewers' invitations were withdrawn the afternoon before after Frances Barber (pictured above), who plays Goneril, seriously injured her knee in a cycling accident.

The director Sir Trevor Nunn said: "Ian and I both feel that the production should be seen in its entirety as it has been rehearsed, and that it would be unfair on the understudy to be reviewed in only her second performance in the role."

Perhaps he is right; but surely there is an argument to be made for having reviewers in to give their opinion on a production the moment that people start paying to see it. Is it fair, for instance, that people going to see The Lord of the Rings in the West End for the first seven weeks of its run should have to do so with no clue about its merits or otherwise? (The first audiences will be there from May 9; press night is June 19.) One of the reasons for the delays is that critics themselves have long been complicit in them. A programme of 'opening nights' across the country (and particularly in London) is fixed to tie in with their movements. The 'first-string' boys (and girls) obviously don't want to miss a 'biggy', and clearly they can't be in two places at once.