Just got off the Explorer of the Seas and here is the story on RCCL cocktail card:
Total cost of card (12 drinks) including tips (automatically added) = $44.85
Average cost per drink = $3.74 only includes basic brands of beer, basic mixed drinks, does not include brand name alcohol or imported beers.
Cost of "basic" drink like bottom rack liquor or drink of the day including tips = $3.74. Gee, isn't it funny that it all comes out the same?!?!? In other words, there is NO BARGAIN with the drink card if you drink the basic stuff.
In fact, there are certain drinks of the day (like the bloody mary's and screwdrivers each morning) that cost, including tip = $3.16.
Cost of brand name drinks can vary - I was charged several prices as follows (includes tip): $5.18 and $6.04. This was for drinks my father enjoys, like Manhattans.
Beer was cheaper by far for the domestic brands - under $3.00 each.
My suggestion is JUST USE YOUR RCCL CARD EACH TIME YOU ORDER. We found ourselves with punches left in our cards near the end of the cruise because it was always a better bargain to use our RCCL card at the moment when ordering. Last day at sea, we were really buzzing trying to drink up all those punches left on the cards!!!
Also, I will tell you that the size of the drinks you get from the cocktail card were very different than if you "paid as you drank". BIG difference. You will find certain bartenders that treat you "better" than others. Just depends if you "click" or not. Like there was one in the casino that made a mean margarita for me and always made too much. He would make me sip down like 20% of the drink, then top it off with the extra mixture, then pour more liquor on top. And all of this in a HUGE glass he would retrieve from the back room when he saw me coming. Whew! Those were mighty fine drinks. I gave him a great tip at the end of the cruise.