This is just a release patch. Technically there's nothing wrong with the codgy old techy's mentality of "always start fresh" there's less reason for it every passing year. You're going to get patches automatically anyway, what you going to do then, uninstall the game just in case? No, you're just gonna let it patch.
The way the patcher works is that it rewrites files and adds those it needs. If there's still a problem, I'd verify integrity before reinstalling the game as it can just re download missing or broken files instead of the whole thing.
So yeah... starting fresh install technically isn't a bad answer, it's just a highly inefficient one.
Then again, I had a similar problem when installing 911 Operator from EA to final release, so yeah, I would add to the "better safe than sorry" guys and tell you to remove everything to avoid any disturbance, I know I will (although it will take 5 minutes to get the complete game so I guess it won't be that annoying for me)
