I rather suspect that the folks at Zondervan/Harper Collins knew two things when they saw Rob Bell's book proposal.
The first being that it would generate controversy. The second being that the controversy would probable translate to sales and they weren't going to let that income go. So waddya do when you've already irritated your prime constituency by diddling with the best-selling bible translation? Bell's proposal was evidently a bridge too far even for the company who's Editor-in-Chief is a founding member of "Christians" for Biblical Equality.
So they shifted Bell over to the secular arm and tossed the hot potato into Harper One's court.
I guess we should be thankful it wasn't published by one of Mr. Murdoch's more openly pornographic enterprises.
ht: Denny Burk