From 7D to 6D. Worth it?

Robert Krawitz wrote:

If you want that, the 5D III offers both in one package and costs no more than the 7D + 6D (and you only need full-frame lenses).

I can think of one plausible use case for this kind of combination: someone who primarily shoots action with a heavy emphasis on wildlife, but who does occasional weddings on the side and wants to have two bodies for redundancy or two different focal lengths, but isn't prepared to invest in a 5D III. They'd use the 6D as their primary wedding camera, with the 7D for backup; for most everything else, they'd use the 7D. But that's a stretch.