If I understood Brandon's video correctly, the pictured setup would get you up and running once you had a jump start.
You would use this if your battery crapped out totally and needed to get back home.
I also read that perhaps the setup would help filter the voltage going to the battery and provide it with a longer life.
Hopefully he'll be along soon to verify this.
This is quoted from one of his posts:
It explains why the bike shuts down when there's no battery. And shows there's no crazy spikes in voltage as someone speculated. The bike can be more reliable with a simple capacitor added to the system, this shows it graphically. I believe it also may explain why they have so many batteries fail (Shitty charging method).