ISF ing is all about setting the front panel controls on the projector to optimum and setting greyscale tracking to optimum. You can buy an optical comparator or video analyser yourself and have a go.(not cheap though....)
ISF certified guys like me can usually offer additional services to get the best mechanical and electronic set up of some units as well
If you go to THE BIG PICTURE web site, Sorry I don't have it bookmarked anymore, you should b e able to find their SonyVPL10/11 forums. On here you'll find threads by a chap who developed a little light meter reading and spreadsheet thingy to help folk with those models to get a better picture. It will probably spark some interest and you may be able to use some of this for your own benefit.
Have fun.
Gordon