Ruin Explorer
Legend
Doug McCrae said:That's all the paragraph is saying - always be aware of whether your players are enjoying an encounter. If not, then move on. Hence the advice "Fun is one element you shouldn't vary."
Considering the lengthy explanation you had to make for it, it's clearly saying it extremely poorly. I have to admit, when I read the DMG, I read it exactly as the OP did, and like him, was confused, given that I had been told whatever was fun, was fun. It's bad wording. It's not going to ruin a generation of players or anything, but it's bad wording.