On one hand I'm totally bewildered a 12 year old can do this (so clean too), and am so amazed.
On the other, my basic knowledge of physics makes this largely unsurprising for a small kid like him to pull this off in today's mega vert world. He has the right size and agility, enough ramp to boost him up, and compounded with his fearlessness to chuck himself up that high.. it's very sensible.
Either way, groundbreaking.