No more than I understand it either 
but it did answer the question. Effectively a completely different encryption algorithm.
This part was interesting:
Furthermore, the connection between peers, which can act as both clients and servers at the same time, go silent when there’s no exchange of data.
Currently I'm using it to VPN into the network from a mobile or laptop client.
It appears there is a way to have the rPi establish their own VPN tunnel between the two networks and connect them at the network level. So if I'm on my home wifi, then the remote network would be a part of the same network without having to VPN from a client. If I'm in public or outside my home network, I could still VPN into one or the other.
This is one thing that Firewalla is supposed to do rather simply through their interface. You also don't need a FW Gold to do it, FW Blue is capable from what I can gather.