That pic doesn't look too different from the video JR recently posted of Feldy's putt on hole #8 of the EO 2011 Rd. 2 part 2 at the 4:49 mark. Also watch Paul McBeth at 5:05 http://www.youtube.com/user/lcgm8#p/u/0/yKyr7AJqTao
I agree with VR's point of power while pushing off. I don't see any baseball pitchers that don't push off the rubber, football QBs throw further pushing off their back foot while striding forward, and most basketball players are better shooting a free throw from a set shot or shooting a set shot vs. a jumpshot (unless its from further out and reqires more power but in my experience still in contact with the ground at time of release).
Sarah Hokom could just be a poser
...in that pic. I think the angle is bad and she's already released the disc with a lot of touch spin plus her follow through is forward due to her jump. She'd call a stroke on herself if she hadn't done it correctly, right?