Sleeves have always been the nemesis of fine couture. Chanel used often to keep her models on their feet for hours on end, pins jabbing into their underarms in order to get her sleeves and armholes, the way she wanted them. Often times, she was never satisfied.
This photo, demonstrates the perfection of a Balenciaga sleeve. Twenty-six couture fittings, were sometimes required, before Balenciaga gave his seal of approval, on a garment. Perfection of line was his obsession; sleeves often ruined the desired effect. In order to achieve the desired lightness to his flou fits, Balenciaga required models to move, while being fitted. He was not able to decide on the fit of a garment, by having a model stand still, before him. Saint Laurent, did the same thing.
When Balenciaga did the uniforms for Air France stewardesses, he asked for a couture fitting for each and every woman: three thousand of them. I don't think his request was granted.