In the past few days, women all over Britain have been declaring themselves born-again customers of Marks & Spencer; led from the darkness of disbelief by the four evangelists for the chain’s autumn collections — Erin O’Connor, Laura Bailey, Noemie Lenoir and Twiggy, the model stars of that omnipresent ad.

But there are other women who are claiming that they never really lost the faith. Here I will confess that it was only the recent withdrawal of the Routemaster buses that caused me to stray from the cult of Marks. It used to be possible to leap from a bus at the traffic lights outside the M&S at Marble Arch. On the way to a meeting I would make a quick detour for supplies of such essentials as Revival skincare, Autograph make-up and Limited Collection trousers. The design of the new-style buses does not permit such acts of retail athleticism. Now, by the time the bus comes to the official stop farther down Oxford Street, duty is calling louder than eyeliner.

Ironically, little and often visits to M&S are now advisable, as there are now more frequent stock deliveries, under the “newness” policy.

With time to spare for once, I strolled rather than scrambled into Marble Arch. Did newness knock me off my feet? Well, I was taken aback by the Per Una skirts hung close to the entrance. The look is best described as Brigadoon on mescaline: tartan, ruched, some with net underskirts at prices from £45. The customers most taken with these items were not twentysomethings, but their mothers. Some of the success of bright, boho Per Una would appear to lie in its ability to touch the inner Edina in fortyplus women.

I was wondering how many Christmas lunches this year will be served by mums in Per Una skirts, when I spied some Italians and remembered the doctrine of my mother, that summa cum laude bargain shopper: “Always follow Italians in a Marks. They’ll lead you to the good stuff.”

I did just that and can reveal that M&S £69 and £79 cashmere cardigans and V-necks and Twiggy-type wrapover cardigans will be worn in Milan this Christmas, probably less of a surprise than the interest shown by the Italians in basic £25 boot-legged and wide-legged trousers.

Some instinct for the not-quite-right caused the Italians to walk past the two most ostensibly attractive coats in all the collections: the £99 houndstooth check, very Sixties, and the £125 Limited Collection tie-belt number, very Marni. But, once I tried them, I felt that neither coat had that something that makes you glad it’s still winter in February. I thought this would still be the case even with the addition of a £75 pair of riding boots, the best in this season’s so-so range. A new coat should enhance everything you already have, rather than require extra expenditure.

The real reason for my visit was not to watch Italians, but to acquire a little black dress. When it comes to LBDs, Es are good, as in Enigmatic and Elegant: qualities the Autograph range should embody. But my enthusiasm for Autograph blusher does not extend to the women’s clothing whose fit fails to justify its price. Autograph’s menswear, advertised by funny guys such as Martin Freeman, is cut to flatter. Surely, after its vicissitudes, Marks knows better than to take the mickey out of women?

Or does it? I was about to leave the store LBD-less, when I caught sight of a black, long-sleeve Empire line number (£39.50), elegant and enigmatic, but hidden among ordinariness, the abiding error of the past. Marks has yet to expiate all of its sins, but you can forgive a lot for a great LBD — and, of course, Limited Collection trousers.

Detail is retail

Layout: Lighting better, but cheap hangers detract from the look 6/10
Staff: Trained to tidy, rather than engage with customers 6/10
Changing rooms: New mirrors make a difference 7/10
Bags: Continue to lack distinction 5/10
Website: Slick online shopping; shame about the dowdy visuals 6/10
Overall score: Getting there, deserves points for effort 6.5/10

The links in the chain

Marks & Spencer, a £6.6 billion business with 400-plus stores, is part of the FTSE100 group of leading companies. Last year, Stuart Rose, M&S chief executive, rejected a 400p-a-share offer from Philip Green, boss of Arcadia and BhS. Subsequently, the shares fell to 319p, but climbed to 397p, after a 3.3 per cent sales rise in the third quarter. Attention is now focused on interim figures, due on November 8.

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