I feel like Riccardo is much more involved with design at Givenchy than the other designers mentioned. Marc has plenty of help at both his own house and at Louis Vuitton, and let's face it, the lines sometimes can look pretty similar anyway. Tom was creative director at both YSL and Gucci, but he wasn't entrenched in the actual design, so he was able to work much, much differently. John apparently didn't do much at Dior by the end of his tenure, so he could concentrate on his own house. And Karl, on the other hand, might be designing and fitting daily with Chanel, but at the end of the day, he seems to design Fendi from afar and is able to show them a series of sketches and have the atelier bring those ideas to fruition without much extra work.