Never seen it before.

I have considered the theory before though. Read and watched a lot of Jim Fetzer stuff on JFK. One thing I'm convinced of is the photo/film evidence was doctored from the very beginning.

My own eyes tell me the motions of the people in the grass median in the Zapruder film are unnatural -- meaning editing took place. And if editing took place, who's to say there weren't multiple takes of "the event?" Anything seems possible these days.