Yes, that method is loose, but it is the only method that you can do with vShare currently as vShare does not offer a "temporary FLV" link. Rather, by default, vShare uses the real link to your FLV files. I have actually made a mod (for 2.6) that uses Lighttpd's mod_secdownload which offers this ability. It isn't fool proof as people can still link to the temporary locations. However, since the location expires, it helps out a lot. Version 2.7 is supposed to have the ability to work with mod_secdownload natively, but I don't know how far it will go with its protection methods.