On 01-04-04 I started a thread (Dice Control: Get Real Get the Feel/ Long) discussing this very thing. The group offering this service is doing it to help themselves (and the casinos) to your money. It is voodoo, bad-bad medicine. Save time, save money, buy a book, study it, practice what you learn, go broke a few times, keep coming back for more. Remember: less than 3% of ALL advantage players make money. If you go to these seminar you get what you deserve. I have no ax to grind. I just hate bull*hitters and con artists.
No decent dice crew will just sit by and let you slide, scoot, helicopter, loft or in any way control the dice. Hell if your real good you might even get arrested or backroomed. Remember what the NRS says; Any person suspected of committing a felony may be detained for the purposes of notifying a peace officer (Gaming). Whether they arrest you or not is irrelevant you will be in their system from that time on. Notifying a peace officer negates the liability of the hotel.
I just can't believe the crap people buy.
Remember what Darwin Ortiz said in one of his books
"you can never cheat an honest man".