The animal is already dead. I think the mode of exit is more an indicator of cruelty. If the animal has been dispatched, then it is really up to the slaughterhouse people and the intended use of the animal.
People that feel very strongly and who are vegans, very often refuse to wear any clothing, shoes, or bags made of leather. Stella Mc Cartney is a vegan and does not use leather in her clothing line, shoes or handbags.
As saddle makers, Hermes has always used leather and has reached the point where they custom order everything from their suppliers so I suspect that they are telling the leather people the look they want in their leather goods. It may be hard to face the fact that to get that look the animal will be bled at a much slower rate. But the animal is already dead, and how long it takes, isn't really an issue anymore.
I suppose the end of this little piece is that some answers to questions are not always very pleasant.