Well, to me it is best to think of any DM campaign like a chain, only as strong as its weakest link. Still, I've always been partial to concentrating on the lists and letting the creative just get done. Even if it sells a lot of product, it could have been crap copy sent to a great list. And, of course, it's easier to sell your boss on your fantastic numbers than on your florid prose. Enter the internet.
Email is cheap and everybody is ready to make millions taking their products online.
You would think that DM'ers would be making a fortune online by now. Of course there's a problem with this assumption. DM'ers can't conquer the Internet because most of them can't conquer the mail. I think they're right. As evidence look at the J. Peterman catalog.