The Making of “Peace for Triple Piano” [video](youtube.com)
I like my original title better: "Vi Hart on how to make a spirally triply meta-chiral time crystal." I didn't make up that phrase. It's how Vi refers to it at the end of the video. I thought it had a certain panache that "The making of..." lacked.
Also, here is the Triple Piano video itself:
Wow, I really had no idea this is what I was watching in the original video. They should consider adding a "This was filmed in one take on one piano" title card!