Can you post some pics?
I'm going to take the "sitting on the fence" approach to this problem.
Alot has changed in 5 years as far as installation practices go. Now I've been sealing systems air tight for years. Many other companies didn't really get into sealing until duct testing & IAQ became important issues (California seems to have the strictest policy early on). There's plenty of systems out there that relied on the 1" insulation wrap to seal the collars. Wouldn't fly today but it might have then.