Yeah that's definitely a possibility. I personally know a guy who took 8 year to finish his Masters degree. It wasn't especially difficult, he's just overly pedantic and perfectionist. But I'd probably ask someone why they took so long to complete.

Actually come to think of it that type of person you describe is perfect for a corporate environment. They want someone that can follow process, not rock the boat, and eventually get something done. Perfect for government too.