The #1 author fantasy I work with in this office says marketing and publicity are the publisher's job, and writing is the author's job. In fact, marketing and publicity have always been author jobs, and the bestseller list is often a reflection of authors who were willing to take those jobs seriously. There are exceptions to this, such as reclusive authors who sell in the stratosphere, but for the most part books do better when authors promote them.
Here's what Jonathan Karp, editor-in-chief and founder of Twelve, says in the April 20 Publisher's Weekly about the matter. He offers twelve recommendations for improving the publishing industry, and with tongue in cheek at the beginning of #8 he says this: We all know that one of the big functions of today's in-house marketing professional is to explain why the publisher can't afford to do much marketing. So who has the money? Authors, from the advances we pay them. Publishers should contractually require that a part of the advance be allocated to marketing and promotional efforts supervised by the author. Publishers, of course, must also do their important marketing work. But authors usually write the best promotional copy (they're writers, after all), and they certainly know their readership best. Yet they are underutilized in the publishing process. Empower them. (Emphasis added)
There are so many things right about this statement that I hardly know where to begin. First, Booklab's recommended proposal model has always included the promise from the author to allocate a portion of the advance to promotion. Second, an author is always the best writer of her/his promotional copy, even if it gets edited in the publicity office. It fascinates me that authors think an underpaid marketing person with a stack of 50 books to promote will somehow write better things about a book than the author will. Some authors are wonderful about this. Others grumble and ask what "their" publicist is for.
One interesting thing to note about excellent book proposals is that much of the copy makes its way to the book jacket eventually. I encourage authors to think this way and write for posterity. You never know when the same copy you wrote to lure an editor to your cause winds up being exactly what a reader in a bookstore encounters, leading to a decision to buy your book.
Academic authors rarely see advances for their work (although some of Georgetown's scholarly authors do enjoy advances -- even large ones!), but even in unpaid instances it makes sense for the author to partner with the publicist and do a lot of work for a book, beginning about six months before it appears. Make an appointment if you'd like to discuss proven strategies for this in more detail.