History isn't better for being jazzed up What galls me - and, apparently, Bennett too - is the pretence of real life that now goes on in these places, to bump up visitor numbers. When he went to Penshurst Place in Kent, home of Lord de L'Isle, he noted the back numbers of Country Life, casually placed next to the drinks table, and the viscount's old hats - his green Guards trilby, his bowler, the lumberjack's headwear presented on a ceremonial visit. This is all tricked out to look like a rare glimpse into real Downton Abbey life - but, Bennett asks, is this just a private room for public consumption? Surely there's a flat elsewhere that is genuinely private. In the play, Bennett takes the over-promotion of the country house to new comic levels, by having the trust hire out Stacpole House to the makers of a porn film. It's classic Bennett: if Harold Pinter's plays revealed the weasel in the cocktail cabinet, Bennett's own cabinet would be stuffed with S & M gear - next to the doilyed platter of custard creams. Of course, the National Trust would never go so far as a porn film - that's the point of comedy, to exaggerate the truth. But, again and again, in real country houses - not just those owned by the National Trust - you come across money-raising stunts that murder the spirit of the place. Kensington Palace, the part-Christopher Wren, part-Palladian house on the edge of Hyde Park, has this year been dumbed down to desperate levels. In the sombre, panelled Queen Mary's Gallery - a rare 17th-century interior in the middle of London - the excruciating screech of birdsong drowns out any chance of quiet reflection; all because Queen Mary was apparently quite keen on birds. Sit on a window seat, and you hear out-of-work actors ramble on in indecipherable Restoration English - to summon up the feel of court gossip. All this is justified on the dodgy grounds of accessibility, with the implicit criticism that olden-days stuff is so boring that you need to jazz it up to get the kids in. As the staggering success of Downton Abbey shows, the British are addicted to the olden days - particularly the posh olden days. The National Trust now has four million members - bigger than any comparable institution in the world. You don't need a kitsch, all-singing, all-dancing version of country house life to get the punters flooding in through the French windows. To be fair to the National Trust, it has done exceptional work in saving great houses for the nation. In an odd coincidence, alongside Bennett's fictional Stacpole House, there is a real Stackpole Court in Pembrokeshire, owned by the National Trust. Well, there was a real Stackpole Court - the charming Palladian house was demolished by Lord Cawdor in 1963, when he couldn't find an institutional tenant. The days of knocking down our greatest contribution to world architecture have thankfully gone - and a good deal of those thanks should go to the trust. Unlike private owners, the trust also has an obligation to preserve its houses and gardens in perpetuity; an obligation that mitigates against the gradual, pleasing crumbling into dust. The dilemma was caught in a 2009 BBC programme on Sissinghurst, when the writer Adam Nicolson - the resident descendant of the donor family - woke up one day to find, to his horror, that the trust had replaced a crumbling, antique stone statue with an immaculate modern copy. The poor old National Trust has to do unlovely things that Lord Grantham - or Lord Carnock, Nicolson's other name - would shudder at. But it doesn't have to eradicate the magic.