I watched these videos on BBC quite a while ago, and I found it on youtube (like any other interesting videos on TV which are uploaded there). The secret is (small-partly) revealed!
The world of haute couture is so mysterious, competitive, and relatively impenetrable. There's a secret club which is more deadly-silent than a religious sect in Utah or deep forest in Papua. It consists of around 200 people (and ALL of them are woman-duchess, baroness, sheiks, women with von and van as their family names, and wives of multimillionaires all around the world) which most of their their names are secret as CIA members. Alike (real) high-class society, they don't like to be exposed, recognized, or known by public that they wear haute couture (how come?). When somebody who doesn't live in it, it's kind of absurd that when you wear six-digits-dollars of dress and you don't want to be publicly seen. But that's the persona of haute couture. The exclusivity. The point of attraction and uniqueness.
Signorefandi, haute couture puceau...