The only part of the NEP that Alberta took to court was the federal tax on oil, and the federal government didn't charge that tax while it was before the court so they didn't overextend their jurisdiction.  It would have been smarter to request a constitutional ruling in advance.  It also would have been smarter to work with Lougheed in advance on the part of the NEP that set oil prices, even though it was within federal jurisdiction, instead of reaching a compromise the year after the policy was enacted.  That's why I say it was not smart to use federal authority to force it WHOLE down Alberta's throat.  Other parts of the NEP like trying to sell Canadian oil to Canadian refineries instead of imports got lost in the controversy, even though that's something Alberta wanted and still wants.

As for BC, just like Lougheed, they have provincial powers they can use to throw a spanner in the works if the federal government simply tries to force the issue.  Goose, gander.