The questioning began at Jil Sander as soon as we sat down - on a plywood set that engulfed seats, walls and floor alike. It was robust, it was raw - it reminded me a little bit of the deepest American tradition of DIY - and it was very masculine. Those were also key points in Raf Simons' A/W collection, but as with the setting, there was far more than first met the eye.

On paper, this was a remarkably straightforward collection. Simons' Sander covered all the bases, offering neat suiting, sportswear-inspired overcoats, a few t-shirts and a clutch of sweaters. All bases, all basics. But as the show progressed, one's eye adjusted to Simon's imperceptibly altered proportions, the torso bulked-up with a roomier, wider cut to shoulders, more volume in the sleeves, and thick, chunky melton wool and neoprenes. Elsewhere, intricate quilting achieved that weight, scrolling stitching across jackets, t-shirts and trousers firming and defining the silhouette.

Sometimes, Simons reverted to a winter classic - layer upon layer of fabric. A sweater sloped at the neck to reveal a pile-up of polonecks, additional layers slipping out at the cuff. Jackets were piled on t-shirts piled on sweaters, and even shoes fusing a moccasin with a formal brogue. The Sander boys, granted, were so slight you hardly noticed this additional heft - so Simons cleverly sliced his trousers close and clean, the shrunken bottom half a contrast to the stuffy masculinity above.

Simons often plays these games with masculine and feminine, and at a time when fashion seems more than ever to be questioning and testing the boundaries between genders, he's still one of the cleverest proponents. Case in point were the chunky parkas: cropped at the waist and multi-pocketed, they seemed perfectly in tune with the workman, workaday environs of the show. But at a second glance, their cut was also reminiscent of mid-century couture, and indeed all that quilting could have been an Abraham Matelasse from a sixties Balenciaga ballgown, especially in shades of apricot and neon-orange. Those were a hang-over from from his much-acclaimed S/S 2011 collections - you can never have too much of a good thing - but here there were subtler echoes of his skills as a colourist in juxtapositions of French navy, black and bottle-green.

Colliding couture and workwear in not only a single collection, but a single garment - and for men to boot - takes a ton of talent, and even more chutzpah. Simons somehow made it look utterly effortless. That's why he's where he is today.

Report by Alex Fury on 15 January 2011.