Very quickly, in terms of keeping up skills, I would leave that aside, but I do think there is a cross-jurisdictional question. A lot of times, locums are about moving across jurisdictions. I think the national effort to develop an application for medical registration in Canada is on the right track, so it is much easier for a doctor to license in multiple jurisdictions now, and it should be.
On February 5th, 2013. See this statement in context.