RE:Happened...
I agree except for the CRA thing. That's an update on old news from an old acquisition. If you are a long term shareholder this would not be a surprise. That's why there are tax lawyers and reviews often avoid the tax courts. Tax lawyers at top accounting firms know a lot about the laws and that's all that matters here.
And the next review decision is in 2 years, and failure them means tax court which pushes this to 2020. By that time, oil will be very different plateau.
So maybe good bashing material for some but not an issue for longer term investors