The guy's name is Sakuta, and there's a ton of YouTube videos of him competing in gymkhana on a GSXS and he does some amazing things on it.
He even has his own website and sells his own brand of crash bars that you see on it.
I have been doing gymkhana where I live since 2008. The GSXS would be great... but you have to accept you will probably crash once every practice session. The thought of doing that to my bike makes my stomach turn. I have a DRZ SM which was built to drop. The skills learned transfer to any bike you ride.
Here's another Sakuta video. He never uses the clutch (he keeps his finger on it, but never uses it). Instead, to circle a cone, he uses mostly front brake (to induce severe lean), maybe some rear brake, and then uses the throttle to prevent the bike from falling to the ground (that fat torque available at idle probably helps). I don't think he ever gets his bike past 4k rpm when he's rounding a cone. Anyway, he executes some of the fastest u-turns and figure 8's I've ever seen.