I agree wholeheartedly that 99.99999% of the crew members work VERY hard and deserve every dime of their gratuities. I guess with me, it's all about being in control of the situation if the unthinkable happens. I, like you, have been on about 20 cruises (6 with Carnival) and only had one bad experience way back in 1982 on the Veracruz.
I'm sorry if my initial emails seem to focus on the gratuity issue. It's not so much my intent to complain as it is to highlight this facet of the tipping program as a FYI.
In any event, the cruise as a whole was great and I would have no reservation cruising with Carnival again....and may just book our next trip next month!