First of all- I totally buy that this video is legit, it would probably simply be easier to actually make all of these kicks than it would be to fake the videos

First of all- I totally buy that this video is legit, it would probably simply be easier to actually make all of these kicks than it would be to fake the videos. Plus, he's not saying he can make that kick every time, he freely admits that it took him many tries, so while it's impressive it's not so superhumanly accurate that it's impossible to imagine. But, if I were going to fake the video, I'd have my kicker kick the first ball for real and mime kicking the second (or if that looks fake, really kick a second ball but paint it out)- and then use the same video physics package this guy used to predict where the balls should be at time t, painting the second ball (and both balls, after they "collide") in, frame-by-frame, on the path it charts out.