I hear alot talk on here about how to tighten pockets. The best way is to extend the sub-rail. For those of you who don't understand the difference click on the link and see a table that was double-shimmed and was redone by extending the sub-rail.
http://s336.photobucket.com/albums/n336/sdbilliards_photo/subrail-extensions/Lynns%20Subrail%20ext/?action=view¤t=e57bcd35.pbw
http://s336.photobucket.com/albums/n336/sdbilliards_photo/subrail-extensions/Lynns%20Subrail%20ext/?action=view¤t=e57bcd35.pbw