Greg Marriott of Apple writes about why Apple decided not to install the disappearing files fix into the System file directly: "Actually, it may seem like a no-brainer to just install the fix in the System and leave it at that. But it gets kind of complicated. The version of the System file is the key. If we don't change the version number after installing the fix, then there is no way for the user to tell if the fix is installed or not. If this is the only fix that we'll ever ship this way, then changing the version number is a trivial (and useful) solution. But since the possibility exists for other fixes being shipped in a Tuner-like delivery mechanism, then changing the version gets problematic. Each succeeding fix could just bump the version number, but what if a user has fix A and C, but not B? This is the point where my brain starts to turn inside out! :-)
It is WAY simpler to have the functionality connected with the Tuner file, regardless of where some of the code really lives. This way, tech support people can ask a question that users can answer in a simple way.
Tech Support: Do you have Tuner 1.1.1 installed?
User: How do I tell?
Tech Support: Look in your Extensions folder for an icon called System 7 Tuner. Select it and use the Get Info command in the File menu."
Information from:
Greg Marriott -- greg@applelink.apple.com -- AOL: JusSomeGuy