I think that is much more complex. In my experience, and Colonel Drapeau can probably elaborate much better than I can, it often requires a very clear understanding of what you're trying to find, even the document name and number. Even then, I've seen exclusions occur that require a grievance because we know it exists.
This goes back to the point that we have developed a more adversarial view of ATIP. It's clear that the government internally does not want to release in certain areas, and you have to know exactly what you're looking for to obtain what you need.
That's my personal experience.