Mad Sanity

I'm trying to do combo 2 of this video, but I keep ending up with 11 hits instead of the 12 in the video. I think it has something with the Inferno Divider hitting an extra time. Not not sure if I'm not close enough to my opponent or what. Does anyone know what my problem is? Maybe try out the combo for themselves? http://www.youtube.com/watch?v=uF-eRzO2kr0#t=0m11s