With multiple agents saying they will look at it again if I put it into past tense.
Given the form's current apparent popularity, that does seem strange. Do they say why?
OK, so what I've got so far is:
1. Before Hunger Games, FPPr was seen by authors and publishers as being a risky choice, and few books were published like that.
2. Then Suzanne Collins used the form for HG, for whatever reason, and the book's popularity made the form acceptable. (Edit, Knife of Never Letting Go predates HG by a few months. I don't know which became a hit first)
3. Now authors feel able to use FPPr if they want, some because it suits the story, some (perhaps) more because it's fashionable.
What I'd really like to know now relates to the first point, and Anya's comment. Prior to 2009, were authors avoiding FPPr deliberately, because it was uncommon? Were they trying to publish in it and getting rejected? Or did it just not occur to most people as a useful choice?