I haven't examined your complex post in detail, but thanks for saying this:
But I think what they [CERA] are also effectively assuming is that those reserves can be ramped up as fast as conventional oil ramps down.
There is this "optimistic" marketing report from Raymond James (warning, big ass pdf file) on tar sands from Alberta on TOD referenced by PG which I took a look at. The bottom line was about 4/mbd from these Canadian sands by 2020. The main message of the report was "invest now!, this is gonna be big". Indeed.
Hopefully you can kind of get the big idea - the data have been marching down the line fairly steadily for twenty years, and CERA is claiming they are about to take off to the upside. It looks implausible on its face.