Good point about the 5th Ave. race, but that was after Webb's best season and it's his best distance. Not sure about how relevant his age 20 Manchester result is, he did beat guys like Dan Lincoln but that was a longgg time ago.
Obviously this upcoming 5k is just to test the waters and I doubt anyone is expecting anything mind-blowing from Webb but I REALLY hope he doesn't run like a 14:20 or even worse DNFs, that would be horrible for his confidence.