Update: The eggcorn has now disappeared, but I am quite sure it used to be there. Damn perfectionists.
So, if we don't think that the McDonalds ad on CBS makes them any more likely to soft-peddle news about obesity, then why should we think that an Amazon associates link makes them any more likely to give a good review to any given book?
Now, I know that there are discovery procedures for finding eggcorns in bulk, but I think I prefer the ones that come by chance, singly, and present themselves as remarkable because of the sense they make. If someone happens—or several someones happen—to write of a "flare for the dramatic" or "bate-and-switch tactics," I don't really care; those examples strike me as just so much orthographic confusion.
"Soft-peddle," on the other hand, at least in this context, has the advantage of being wrong in a meangingful way: the post is about advertising, and so the piano metaphor "soft-pedal" goes out the window in favour of something that looks like an antonym of "hard sell."