only providing the suggested mirror to use....this is nothing more then and a websever.... Shoot even the WBEL guy is having yum hit his tiny T1 to get the mirror list.
In the event that the central site or network is inaccessible then the entire system stops. Even if there is new data on all/any mirror.
That's a good reason to have multiple mirrors populated in the config file.
or you can use a mirrorlist file but put it ON the machine.
-sv