If you aren't comfortable with it and you are having the traditional dining, just go to the purser's desk and ask for it to be removed from your charges. Then you can tip the normal way. They did it for the personal choice diners since they could be geting a different waitstaff every night. As for reviews of this, some people love it and others hate it. I'm sailing Princess twice in the next couple of months and I'm going for traditional as well. I like sitting with the same people every night. Usually I like them very much and enjoy having a meal with them.