I'm from Finance. Maybe I'll take that one.
RRSP strips are a good example of something on the border between evasion and avoidance. Some of the first-generation structures were so aggressive that CRA argued that, under existing rules in fact the tax plan was not effective and just not legal, and that would tip you over to an evasion category. Nevertheless, the planning was quite widespread and promoted. It got more sophisticated. The more sophisticated versions of the plan exploited weaknesses in some of the rules, and then you were into avoidance.
Budget 2011 introduced new anti-RRSP strip rules, which were clearer and more specific and which carried more serious sanctions. I'd say that now the issue has been addressed. Whether it was a case of evasion or avoidance before, it's now quite clear under the law that the plans are not effective.