Joan Rivers @ Edinburgh Fringe

If there’s one phrase we Westeners cling to as our civilization slides down the Olympic-sized slalom course to hell, it’s freedom of speech. It doesn’t matter what we have to say, or that we’ll kill to say it: the basic democratic right to parade our kids in front of clinics dressed as aborted foetuses proves that we’re fundamentally moral. And quite right too.

However, one unfortunate casualty of our defensively aggressive eloquence is the dying art of discretion. With its overtones of gentlemanly restraint, discretion is a casualty of class politics, perceived as a spin doctor for spiffs. Christine Keeler branded discretion ‘the polite word for hypocrisy’ and nowadays the word carries a whiff of talc and evil, like a kid-gloved emotional butler, quietly cloaking the debauchery in the buttery to sustain the status quo.

Of course, desperately aspirational animals that we are, this means that discretion’s ripe for a comeback. Indiscretion has nowhere left to go. With his new memoir Life With My Sister Madonna, Christopher Ciccone does the literary equivalent of scavenging celebrity rubbish for nail clippings to sell on eBay. Having barely recovered from finding Piers Morgan’s risible ‘insider’ diaries in our stocking, do we truly have the stomach for ex-Heat editor Mark Frith’s imminent tell-all – from the same agent, publisher and editor, to boot? After all, his magazine, once an unstoppable zeitgeist behemoth, is finally stumbling to its knees like a semi-clad chav drunk on cheap gossip.

When everyone has a blog and a slot on MTV, there’s much to be said for shutting the fuck up. To be discreet is also to be discrete: detached from others; separate; distinct. It denotes a kind of self-contained excellence, an ability to swallow your tongue rather than spew your guts. Sir Walter Scott, perhaps a more reliably insightful (although sadly less reliably naked) source than Ms Keeler, considered discretion ‘the perfection of reason’. Are we secretly crying out for the renaissance of restraint?

Not according to Joan Rivers, whose new play cum standup A Work in Progress by A Life In Progress, showcased at the Edinburgh Festival and coming to London last month, only confirms her status as the brash, plastic-faced poster girl for immoderate mouthing off. Effectively a one-woman elegy to the insecurity of an ageing life in ‘the biz’ (despite attempts to graft her ramblings onto a limp and unnecessary playlet), Rivers’ show is peppered with portraits of those she has adored and abhorred along the way. This offers both predictable pleasure, when she lays into staple scapegoats such as Victoria Beckham and the Olsens, and more heretical thrills, when she attacks the likes of legendary fifties cinematographer Lucien Ballard.

Her wit is as clever as ever, but the snipes increasingly feel a little bitter, a little bland. What sounds shocking on daytime ITV simply seems tame in the midst of the Fringe, that scene of competitive iconoclasm. An audience that has just seen the Frtizl kids do the Sound of Music in a News Revue sketch is likely to be underwhelmed by Rivers’ revelation that Johnny Carson was a cad. But Rivers’ lame sniping is harmless compared to her self-serving sincerity. In one tale she details her dinner parties with the ancient, ailing Mae West, where assembled acolytes would sit in virtual darkness on the insistence of the crumbling star, while West grandly repeated the same four anecdotes, prompted by the muscle-bound young boyfriend at her side, reduced to a threadbare performing monkey. The searingly sad image is only really conjured to vent Rivers’ own feelings of guilt and fear. She may criticise West’s old hangers-on for failing to attend her desolate funeral, but at least they left her memory intact.

We’ll always crave revelation, and our licence to spill is one of the joys of enlightened times. Beneath every circumspect sophisticate, Chanel boucle jacket carefully buttoned up to the chin, is a greedy gossip whore fighting to escape. But indiscretion is often a true sign of insecurity, a bid for importance or moral superiority on the part of the tale-teller, and it’s wearing a little thin. So this month give Rivers’ show a miss; instead, read Remains of The Day, Kazuo Ishiguro’s paean to English understatement, and re-watch Goin’ To Town.