I have read lots of info on this subject (I need to as we don't tip in Australia) and from what people are saying all monies, whether you pay cash direct or auto account, it is all divided up according to a set of rules (usely by the Maitre'D) and distributed according to who does what on the ship. If you have the auto tipping and you want to give something extra to a person who is outstanding in their job that money still goes (supposedly) into the same pool of money at the end of the cruise. So in reality you are just paying extra to all staff. On the other hand if you get poor service don't just not tip them, let someone know about it ie. the Maitre'D!