Resistance to the new workflow!

We have had our XSAN working for about 10 months. We have 4- FCP clients. I am still having problems with a few of our editors storing projects and media files on the desktop or other locations other than the XSAN. Everyone has their own folder on the XSAN that is protected with affinities, but they are still storing stuff on the local drives. As you know, this throws a monkey wrench into the whole "shared workflow" plan. I have tried "tweaking" the permissions on the folders of the local machines, but it causes problems with other applications.I have also tried using Workgroup Manager, but there are not many tools there to do what I need. Is there an easy way to lock access to the local drives so only the XSAN can be used? Is there any third party management software that might give me more control over the XSAN?

KCLV City of Las Vegas