So Meghan Markle is 5ft 6in, maybe 5ft 7in, says the internet. I Googled this because of a coat she wore, one day last month on a walkabout. It was oatmeal, single-breasted, by the Canadian tailoring label Smythe. It’s sold out now, naturally, but that’s not the point, because it wasn’t so much that particular coat I was taken with, nice though it is, so much as seeing a long-line coat trend work in a non-catwalk scenario.

Long coats invariably look incredible when you see them on the catwalk. A strong shoulder, a weighty fabric and a calf-length hem create a lean, dramatic line. Plus there is an air of romance and intrigue that you just don’t get with a padded jacket or a sensible three-quarter-length. This is the coat you’d wear, surely, for a long kiss goodbye on a station platform. It looks marvellous when it sweeps past you on a catwalk, on a model with bouncy, blow-dried hair nudging 6ft.

But in real life, a long coat can trip you up in more ways than the obvious. If you are of average height, it can look droopy and shapeless, so the effect is less Robert Doisneau and more Robert Smith. Also, the classic catwalk cheat is to offset the practicality of the coat with high-maintenance styling, so a long cashmere coat will often be styled with the kind of party hair that isn’t a viable everyday option for most of us, and shrugged back over the shoulders to reveal the lace edges of a silk camisole and a smidgen of clavicle. I mean, I ask you. Sometimes I wonder why no one at fashion week has ever grasped the simple principle of buttoning your coat before you leave the house to keep the warm air inside.

Whereas Markle had her hair in a messy bun, and a scarf on. (I do like the cut of her jib.) Most importantly she is, as noted, of relatively average height, although she’s got a good inch on me. So I am taking a styling tip from her here, which is to wear a long coat with an even longer layer beneath – wide trousers in her case, a full-length sweater dress in mine. It turns out it helps, because it reminds the world that you have legs. Average-length legs, yes, but legs. What you need to wear a long-line coat is not more inches of height, but more inches of the outfit underneath. Aim high: a long coat is within your reach, after all.

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