I don't speak for every use case. I'm speaking for a use case that has been ignored. I can't believe you'd release a $600 closed headphone with better imaging and soundstage, in a market that has a severe lack of such headphones, and not realise that perhaps some people may want to use it portably.
Well, You already can use it portably. what you're asking for is a cable that makes it more convenient. If convenience is a top priority, I am not sure why you would use the AD's in the first place. They are not a very convenient option for portable use, even if they had a more convenient cable.
However as you can see from Dan's post above, he is all for making the cable, if he feels enough people really would buy it.