Combines 9650 sts over 9750 sts

I just now read this whole discourse on the Deere STS machines. If Deere doesn't recommend running a 12 row head on the 9650sts then I have to wonder why at the DuQuoin,Il Agriland this year Deere brought a 9650sts and ran it in the field demonstrations with the 12 row corn headIJ

The JD STS may have more power and a better tri-stream feeding system which tends to make it an improvement over a CIH in damp tough straw conditions. For real performance in these conditions the super conventionals like the Cat lEXION with its APS or the other yellow NH TX combines are able to handle the tough crops including green stem beans better.