Hello,
no changes required - the user "just" has to go to "User Homes" => "(Name of user)" and he is in the right space.
Ok - you can actually configure the root path of the WebDAV servlet via alfresco-global.properties (property "system.webdav.rootPath"). But you can't make it generic e.g. have it react to the user that is logged in. On the other hand, if you restrict the root path, you essentially render WebDAV unusable for anything else than just uploading files to "My Files".
Regards
Axel