The duck talks and wears spats, and the inaccuracy you're concerned that gold is too dense to swim in?

I'm amused people think that this is some sort of vote.

It's probably real. Things happen at ultra-high speeds that are counterintuitive - like the compression waves you see in this video. Someone noted a golfball will crack in a vise - and it will - but the situation is not the same, in that the vise is steady-state, while the golfball in the video is free to oscillate and turn that energy back into kinetic motion.

The way to confirm reality would be to simply reproduce the video; the one attempt I saw above still wasn't nearly fast enough to show anything. Calling the Mythbusters!