Just out of interest, I decided to try Exblend() v1.03 Beta2, and it seems to be producing a reasonable level of success (about 94.0% blend detect [EDIT: Ideally about 96% or more]).
Although your sample is somewhat static (not much movement so not really good short clip for testing).
Here:-
http://forum.doom9.org/showthread.ph...hlight=exblend
ExBlend not intended for this type of blending, but seems to be working OK.
EDIT: