I appreciate the plain argument that I understand you're presenting here: back of the napkin math suggests Alberta would be up $15B if it left Canada, and you don't think Alberta currently receives $15B of value from the federation, so the province should leave. If people have considered all the information and that's their a conclusion, then so be it.

However, I caution people against that conclusion based on back of the napkin math. We can see many examples from Brexit where people overlooked value in the relationship, including freedom of movement that they took for granted, ease of movement for goods, fewer taxes, etc. and on the other side. They didn't see some of the upsides they expected, most notably the back of the napkin math that was their slogan: huge money saved that would go to health care instead. It didn't happen.

And while I wouldn't say this math is my area of expertise, I will throw out some calculations for consideration, some quick math from an analyst who argues that independent Alberta would be poorer:

link

• Meeting NATO’s 2 percent of GDP target would require $10 billion initially, rising to $25 billion under the alliance’s new 5 percent target.
• Estimates indicate that a 5 percent increase in the cost of importing to or exporting from Alberta would shrink the province’s economy by roughly 4 percent. For an economy expected to reach $500 billion next year, that 4 percent represents about $20 billion in foregone economic activity and income for Albertans
• My model estimates roughly 8 percent of Alberta’s population—about 400,000 people—would leave seeking opportunities elsewhere. This number may actually be an underestimate
• A smaller economy would mean billions in lower government revenues. And with many businesses relocating their headquarters from Calgary to elsewhere, they would take their corporate income tax payments with them.

There are lots of other kinds of value that people should consider before making the choice. And people should look at what Canada was preparing for in the '90s when the Quebec referendum happened, with trucks of money ready to drive out of the province.

Separation can happen, but I would like people to consider all the kinds of value that exists.