The problem with most plays you see in the theatre is that the main character doesn’t appear immediately. Playwrights like to keep you in a bit of suspense. They like to crack their knuckles and flex their tendons before letting rip, do a bit of scene-setting, throw you the odd red herring. They like you to be murmuring to yourself, “Who is this Hamlet fellow, I wonder, of whom the title speaks so highly?” while assorted spear-carriers and insubstantial pals of the main man shuffle about on stage, bumping into things and asking each other who they are.

The result of this is that the first few lines of the play are generally spoken by someone who isn’t good enough at acting to have landed a decent part.

The beginning of a play is the worst bit. The lights go down as you shuffle out of your coat and wedge it under your thighs to compensate for the unwelcoming downward slope of your busted seat; a dozen square little light-pads flicker as the troop of schoolgirls next to you, who are doing the play for GCSE, reluctantly switch their iPhones to vibrate and send last-minute “am in feertur” texts to stoned, saggy-jeaned boyfriends back in Croydon; the fat lady in front leans discreetly over on to one buttock to release a small, grateful “parp” that she hopes will be drowned by the sound of her rustling in her bag of Murray Mints; stagehands scuttle darkly for the wings like disturbed suburban burglars; the lights come up, and someone who is not Kenneth Branagh, or Simon Russell Beale or the bloke out of Doctor Who, nor will ever be, limps to the front of the stage (is that limp part of the character or did he prang his foot with an edging tool that morning in his day job as a gardener?) and shouts something.

It’s such a shame that the most difficult line of all, that first throat-clear into a silent hall, the line which sets the tone, volume and balance for the evening, should so often be placed in the mouth of the guy who will sell you your half-time ice cream. Within seconds, you’re looking at your watch (“Two hours to go? Still?”).

And from then on it’s just embarrassing. And incredibly stressful. I simply cannot watch for fear that somebody will forget his lines, or fall over. Bizarre, that such a linchpin element of our culture should come down to a feat of recall – Shakespeare rolling out of some old ham, one word at a time, and only the skills of a fairground memory man separating art from the abyss. Like asking Leonardo da Vinci to perform live, under Rolf Harris conditions (“Can you tell what she’s smiling at yet?”).

A two-hour memory trick, plus yelling, spitting and a bit of running about. And most of the time you’re busting for the loo. And the only way to get through it is by thinking about what you’re going to have for dinner. If you’re at the Old Vic, then you get through the last hour of Ibsen dreaming of the Lancashire hotpot you’re about to tuck into at the Anchor & Hope, if you’re at the National then the finale of any play can be brought on with the thoughts of a nice chicken pie at Canteen (you cannot stay the hungry edge of appetite with bare imagination of a feast, it’s true, but you can sure stay the boring bits of Pinter with it), and if you’re anywhere in the West End, then while the mummers mum their worst, you can always drift away to Sheekey.

Ah, J Sheekey: a seat at the burnished bar, an icy glass of riesling, the rattling blades of razor shells beneath a pile of yabbering clam flesh, broad beans and slices of hot, oily chorizo, a screw of chewy white bread, a slam of slip sole, brown shrimp, eggy roe and a spray of bright lemon through clean white muslin… and before you know it, you’re into Act V, the irritating beardy man with the booming voice is dead, a number of misunderstandings have been resolved, the hunched and fag-smelling critic on the end of your row has bolted for the exit and any minute now the cast will be holding hands and bowing. A quick wee, and three minutes later you’re actually there, walking in through the door.

At Sheekey there are no faltering first lines. The boys on the front desk twinkle and shine like the stars of the show they are. And they treat everyone who comes in as if they were famous, because they usually are.

I was in the other night after a really wonderful performance of A View from the Bridge, with Ken Stott as old man Carbone, to check out the new oyster bar which is attached to the existing restaurant, stage right, and provides, around its sprawling horseshoe counter, loads more seating for impromptu post-theatrical show-ups.

It’s bang next to the old, straight-line bar, and while it does a great job of relieving some of the strain on an unfeasibly popular restaurant at busy times, I suppose it does fractionally diminish the thrill one used to get at sneaking on to one of the precious spare stools at the old original. But only the most tremendous snob would suggest that the supply of space at great restaurants should be artificially controlled, like the diamond market, to ramp up desirability. Which is why it falls to me to do it, if only half-heartedly.

The oyster bar offers a wide selection of smaller, picking dishes, rather than the full menu available at the original, which I did not immediately grasp, and so ended up eating five courses: the razor clams (always), followed by a tapas-sized portion of octopus with rosevale potatoes and capers, then the potted shrimps (as I moved off sherry on to a glass of gavi), then, still peckish, a bulging Welsh rarebit and then a share with Esther (who had, meanwhile, had only a modest saucer of deep-fried goujons) of the meatiest, muscliest spotted dick in history, with a firm slap of golden syrup and custard.

We had six dishes, then, and five excellent glasses of wine, for £92 including service. Which is not bad at all. But the real value comes in the hidden, unpriced extras.

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