I don't know who the folks are you worked with, Nomad, but when I was at MH-Professional we started promotion the day after the contract was signed. Hundreds of thousands of direct mail, space ads, newsletters, and sample copies (bound page proofs) went out months and months before p-date. Even when we pitched another book on the same subject, we managed to include the up-and-coming books in a another brochure or booklet in the same package.
I also liked the folks. They were friendly and helpful.
Don't know about the other divisions.
dp