I've seen a few people forward this premise now

I think it's bogus.

A better way to look at this is that the Eagles quite obviously have been impressed by Wentz from the day he stepped foot into the building. They maintained that they weren't planning to start him any time soon, and they probably meant that......for a short while. But it was Wentz himself who changed that thinking and when the opportunity presented itself to get him on the field sooner than later, they jumped on it.

It is probably closer to the truth to say had Bridgewater not gone down, the only reason Bradford would have been starting for the Eagles and Wentz not was the 2nd round pick they gave up for him and the $20M they didn't want to see languishing on the bench along with his trade value.