IMO i don't think its easy to do it well enough to get an advantage, however i don't think it's Impossible, just unlikely.
http://crapspit.proboards25.com/index.cgi?board=setting
Check out that link for all theories both ways on whether dice setting really works.
laslty on the whole thing about hosting gambling signings and classes at casinos. They are actually good for casinos whether they work correctly or not.
The reason being that probably over 90% of the people who try these things don't take the time to learn everything and rush into it and do it incorrectly that they more than make up for the people who do it so well that they win a little bit.
i can't find a link to it but on a special i saw on thorp they said that due to his book release the number of black jack players sky rocketed in the casinos as it helped increase the populairty of blackjack. Many novice counters applied his theories incorrectly and gained no advantage of the casino and simply lost money they would not have if they hadn't read his book.