Every barrier that slows down attacks a little is worth it when you are trying to buy time so people can apply emergency updates. It's not about stopping them from ever figuring it out.

they're just delaying it by two weeks...

Depends on skill level and the exact nature of the flaw. There's definitely going to be a nonzero number of malicious people who lie in the middle distance "I can come up with a way to exploit flaws if I have a detailed trail of breadcrumbs" and "I can't be bothered to do an unlimited amount of work to track down how to do this, I have other malicious things on my schedule for today."