Margo's idea about contributing to the crew welfare fund is a very good one.
As for other tips, here is what I've been told by RSSC Hotel Directors. Consider the stewardess' job description. If what she does for you is within that job description, your tip is included in the fare. If however, she does something extra for you (running an errand, etc.) a tip would be in order. Were general tipping to "get started" on Radisson and become known to the cruising public, this would place Radisson in a delima. It would make their statements about "tips included" false. It would put them in a competitive disadvantage with Silversea and Seabourn. And it would raise the question which has no good answer about what to do with stewardess' salaries.
On our first Radisson cruise (moving up from mass market) I naturally found the idea of not tipping for such good service very unnatural, so I specifically asked the Hotel Director for advice, due to my desire to go with the program. The above is what I was told.
Thanks,
Richard :) :) :)