"The Canada Revenue Agency has significantly disenfranchised the tax avoidance/tax planning right of a tax payer by developing a general anti-avoidance rule (GARR), a vague provision that allows the tax agency to disallow a tax benefit if the tax payer's avoidance measure "abused" the Income Tax Act."

IMHO the wrong turning in UK tax law was taken when the maxim "there is no equity in a taxing statute" was adopted. I thought it came from IRC -v- Westminster, but I maybe wrong. What there is, certainly, is a purpose.

In my view, tax evasion involves escaping the purpose of taxing statutes. Whatever steps are taken are taken with a view to reducing the payer's liability from what it would otherwise be, and thus the tax revenue raised below what it would otherwise be.

In all other statutory interpretation "the mischief rule" would allow the examination of purpose and the application of the statute so as to give effect to that purpose.