Dior's New Look skirts were reworked in iridescent ballerina-length silks with huge blowsy embossed roses, or chopped into tiny mini pouffes over shorts. The classic Bar jacket, which, Simons later tells me, Dior created for women to wear to the bar in the Plaza Athenee at 5pm, was restructured as a strapless tuxedo and slipped over skinny men's trousers and arrow-head stilettos.
In a month of big deals (Hedi Slimane's debut at Saint Laurent; Christopher Kane and Mary Katrantzou's mega-smashes in London; Jil Sander's comeback in Milan), this was by far the biggest.
Simons' small couture collection two months earlier, whisked up after he'd barely been in the job six weeks, had been rapturously received. But couture is a rarefied ledge high up the mountain and the air can cause euphoria. Lower down, on the plains of ready to wear, it's saner and tougher. You have to thrill, but you must also sell. You cannot send out a "bijou" collection. You must wham-bam them, even if slow seduction is more your style.
And afterwards, just when you feel you want to collapse, you cannot hide from the throng of socialites, journalists, bloggers, retailers, walkers and liggers who will push past those bouncers and encircle you, tornado-like. You must smile and answer question after inane question while the tornado works its way to a genuine fashion frenzy. Because that's what you signed up for, right?
There are those who wonder whether the independently minded, privacy-valuing Simons knew precisely what he was signing up for when he accepted the industry's biggest job going - one that came with a certain amount of, shall we say, baggage? But he's far from the Antwerp-based hermit he was often painted as when he was working for Jil Sander in Milan. He still lives in Antwerp (no backwater city, he claims) in a fabulous mid-20th century house with huge windows on to the world.
When I meet him, post-show, in the elegant Dior-grey drawing-room above the Dior HQ on the Avenue Montaigne, he is at pains to point out that he was never reclusive. "Yes, I'm shy but not on a one-to-one basis. Over the years I have become acclimatised to a bit of publicity."
He is contained, however, and thoughtful, visibly processing ideas and opposing views before delivering his opinion - as befits someone who once taught fashion, back in those far off days when he was designing one solitary man's collection a season, under his own name in Antwerp.
He did look a bit shell-shocked after that first ready-to-wear in September. But most of all he looked for his parents. Everything else could wait.
While the socialites, celebrities and bloggers swarmed and journalists tried to stall their news desks, Simons darted through the crowd until he found his mother and father. In a brittle, often superficial and always restless industry, their mutual embrace was genuinely touching.
He has previously said his parents are very "holy" to him - a striking remark. His father had to go into the army at age 16, and stayed there. Duty, loyalty and discipline run in the Simons family. But they never, he says, told him what to do.
School - a strict religious establishment where he was taught by priests and expected to take weekly confession - did that for them. "I really didn't do many bad things, so after a while I just made things up."
It was a very small, sober village. "The only creative outlet was the record shop." To this day he has particular tastes - embodied by Kraftwerk - which he indulges in the Dior shows.
"My mother was a cleaning lady all her life," Simons says, sprawling on a sofa in the grey cocoon. He is dressed in his habitual khakis. A big bowl of fat roses sits on the table between us like an aromatic shield, although it also looks faintly incongruous with his slightly ascetic air.
At 44, arrestingly blue-eyed, tall and crop-headed, he still somehow looks like a boy scout.
"She didn't have many opportunities to indulge her creativity but she was always arranging bouquets of flowers for the whole street."
The fragrant banks of peonies and lilies that lined the walls of the adjoining salons where he showed his first couture collection for Dior were a tribute to her and to Christian Dior, who was also partial to flowers. "I have created Flower Women," Dior exclaimed on examining the slender, stem-waisted skirts of his New Look in 1948.
It transpires that Simons - the great modernist, often hailed as the "future" of fashion - had been studying old Dior for some time. His final three collections at Jil Sander increasingly borrowed and updated Dior tropes - the icy 1950s pink (now, largely thanks to Simons, one of 2013's big colours), the flared duster coats, the elbow-length gloves, the veils and of course those sweeping, calf-length New Look skirts, culminating in his lushly elegiac Mad Men-esque final collection there.
Simons insists his fascination with Dior blossomed way before the Dior job ever came up, partly, he confesses, because everyone else at the time was so consumed by Cristobal Balenciaga, Coco Chanel and YSL.
"What struck me most," Simons observes, "was that the New Look had a kind of Belle Epoque point of reference, but the constructions are ingenious, architecturally. The more I analysed the pieces the more I realised how many people have built a career on Dior's patterns, from Yohji Yamamoto and Commes des Garcons onwards. What he achieved in 10 years at his house is unprecedented."
What Simons has so far achieved is also impressive. At Jil Sander, a label that had been floundering since the departure of its namesake founder, he forged a new aesthetic that was streamlined yet intensely feminine, luxurious but pared-back, restrained while frequently drenched in delightfully unexpected colour mixes.
The only pity was that Jil Sanders' owners omitted to manufacture most of it: those sleek, contemporary, intelligently conceived clothes would have made a lot of career women, and not-so career women, very happy. In an industry that doesn't readily jump to its feet to applaud, his final show earned an ovation.
It's history now, even if it was immensely frustrating for him at the time. "I felt more like a psychiatrist than a designer in the end, just to keep my team's spirits up," is all he'll say on the record.
But Simons likes being a shrink. Dissecting the algorithms of design and putting them in the blender with psychology, music, politics and the arts makes his job interesting.
"He'll have weighed up the Dior job carefully," says international branding consultant Joy Yaffe who, in 1999, hired Simons and his then girlfriend Veronique Branquinho for a two-season tenure as the men's and women's wear designers at Ruffo Research, then a cutting-edge leather house.
"While he'll want some privacy, he understands the importance of accessibility in a brand like Dior and he's learned to live with that."
Watching a modernist, who began his career as an industrial furniture designer, reinterpret the codes of a romantic shibboleth like Dior, a house that was steeped in nostalgia even at its launch, will be fascinating. On the evidence so far, the gulf between Simons and Christian Dior is far narrower than anyone might have imagined.
"Raf is a natural iconoclast," the journalist Tim Blanks says, "but he's also a fan. He loves fashion. He still raves about seeing his first fashion show when he was working for the Belgian designer Walter Van Beirendonck. They'd gone to watch Martin Margiela and Raf was blown away by what fashion could be."
Perhaps it's the fan in him that explains the following. After I'd leapt up from my seat, been escorted and jostled, I had to leave before asking Simons my questions in order to make that final deadline. But in the taxi back to the hotel my phone rang. It was the PR. Simons had remembered seeing me in the crowd and wanted to answer my questions now - which he proceeded to do with methodical clarity and courtesy. That's not what happens at your average mega-show. But let's hope it is the future.
