Watching the video the bike looks to be inherently unstable even when rolling forward. The rider is using his body to control the direction of the rear wheel a

Watching the video the bike looks to be inherently unstable even when rolling forward. The rider is using his body to control the direction of the rear wheel and corners look pretty shaky if you don't keep the alignment right. It may have fewer parts but to my eye it looks like it has more ways this could go very wrong. Sort of like when you are pushing one of those rolling dolly's where all 4 wheels rotate independently.