The critical question isn't time; the critical question is information. That is to say, on what basis do you review your five minutes? If you have a complete or a reasonably complete file that has been vetted by someone who understands the nature of the file itself—and that would not necessarily be a visa officer.
One of the things we're considering is actually having intelligence officers, in this concept that doesn't exist yet, vet those files. We see that as a more effective means than allowing somebody to arrive in Canada, and then spending an inordinate amount of time and money trying to deal with the consequences of that arrival.