Are you making the claim, then, that there's absolutely no overlap between the fields of marketing and design, that conversion is solely the responsibility of m

Are you making the claim, then, that there's absolutely no overlap between the fields of marketing and design, that conversion is solely the responsibility of marketing, that conversion is completely uninfluenced by design, and that being able to fill multiple roles is a waste of time for everyone involved? Otherwise I'm having difficulty following your train of thought here.