Folder Redirection: What does the “Also Apply Redirection Policy…” setting do?

When implementing Folder Redirection via Group Policy, there is a checkbox on the Settings tab that says “Also apply redirection policy to Windows 2000, Windows 2000 Server, Windows XP, and Windows Server 2003 operating systems.

When I Google this checkbox, all I find are how-to articles on folder redirection in general, support articles saying one bad thing or another is happening because it is or isn’t checked, or forums full of advice from people clearly have no idea what they’re doing.

I know how folder redirection works. I also know how to read. What I want to know is, what does this setting actually do from a technical standpoint?

Folder Redirection - Documents Properties

We do not have any XP or Server 2003 machines in our environment, so this checkbox is irrelevant to me. But today I found a rogue group policy that is screwing up permissions on a file server, and it’s because it had the “Grant the user exclusive rights…” checkbox enabled. I need to disable it, but that policy also has this option set, and I want to know how/if this will affect the terminal server it’s being applied to.