I think this is the one that we saw in motion with the women duplicating the motion quite nicely. I think Yoda commented this as well - somewhere on the forum. BTW - there is a swedish film called "Den ofrivillige golfaren" that has some sort of old swing plane device that he golfer stepped into and got the swing going back and forth for several minutes continuously.http://en.wikipedia.org/wiki/Den_ofrivillige_golfaren Found this one:
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