It is very simple, and it goes like this:

1. Alberta is developing the sands and raking in the oil money as fast as it can.
2. The amount of oil sands in Alberta is not infinite.
3. When the rigs dry out, all there is left will be the disastrous environment impact and attendant clean-up bill.
4. The Environment falls under federal jurisdiction.
5. Just as Alberta is reluctant to share the wealth, it will be quick to foist the prohibitive clean-up bills on the Feds.
6. Meanwhile, thanks to Alberta, the rest of the country is slowing down the pace of economic growth in order to meet Kyoto targets.
7. Ergo, Alberta will bankrupt the Government of Canada in 50 years.

However you cut it, it is a rotten deal for the Feds. I say, let them go now, before it is too late.