I have always had a fantastic time at CTI and never felt anyone was waiting or expecting a tip. I know they have a no tipping policy and I've never been made to feel like that is "optional". I do read TA reviews but I tend to look at it more as a whole. If, overall, the resort has good comments, I tend to go more with those than the negative ones. I like to read the negative ones, usually more for fun, to laugh at how unreasonable some people are.
So, like so many others have said, take the reviews with a grain of salt and trust what the majority or reviewers wrote and have a fantastic trip!