This thread is very old, But,
Jocelyn passed away Friday June 3/2016 with complications from being quadrapalegic , pnemonia, breathing.
We've paid some over due tributes to him here in Canada.
Regarding the two gear bike. Both Jos and I received a photograph from some dude in Holland or Denmark in the early winter of 1979.
The pic showed this two gear Kilo bike. He wanted us to purchase one with a verbal guarantee that it would help our Kilo's to become faster.
The idea sort of died. Later that summer Jocelyn emerged at our Nat's with a two geared bike that he built himself.
The system worked like this. The drive train on the right side of the had your chosen gear. The rear sprocket was mounted with only one turn of the thread to tighten it up. As you begin to pedal the sprocket would tighten up. The drive train on the left side was threaded opposite. You started the Kilo with a smaller gear that slowly untied itself when the larger right hand side gear locked into place. The theory was to allow you to start with a smaller gear for perhaps the first 75-100 meters.
Bottom line was, it didn't work, Too much transition when the larger gear kicked in. It felt like you were doing two standing started back to back.
Jocelyn was definitely an equipment genius though, I'm going to miss him. Gordon