Well, to an extent, it's because these things *are* vague. That's part of the "joy" of publishing. You never know what's going to work out well or horribly, no matter the concrete actions of writer and publisher.
I'm currently under contract with them. I have not/will not investigate(d) my sales numbers. I'm a newbie nobody no one has heard of and I don't have FSOG-like expectations of a bajillion copies sold. (Dreams, yes, expectations? No.
) That said, Nola's experience is not quite mine. I was given a super-detailed publicity plan, an awesome cover, social media graphics and teasers, as well as their work behind-the-scenes to increase my exposure via romance blog sites and FB. It wasn't just them; I had to do a lot of work for it, myself. Blog posts for guest blogs, FB takeovers, etc, and I can't say I feel it helped a ton, insofar as I didn't get a slew of reviews or people signing up for my newsletter out of them. But I'm fine moving at more of a turtle pace, than hare, and the publicity team has been very supportive of me when I ask for help.
Entangled promo does move on week-to-week, so the intensive help does fall off 3-4 weeks after release, but I'm not sure that's atypical. They are still working in the background for me, because I have a second book in a duology coming out, and an unrelated novel contracted for ?? release. It's still in their interest to support my books if the idea of building a tail really is the way to bear fruit.
Maybe it's that my expectations were not as lofty as they might be if I had an agent and had signed with a Big 5 imprint, but I have been satisfied thus far. (And yes, my editor has been extremely professional and has let my work be
my work (not hers), and the production team has been responsive and easy to work with.) It hasn't been all perfect, but I don't assume any writer/publisher relationship is. Consider that, with some publishers, writers don't see the warty moments because the pubs only work with agented authors. The agent gets the brunt, and tempers it as needed.