Wearing once for the first 5 or 10 minutes, just to make sure the fit is right is ok. If you are already sure the fit is right then no need. Any joker wearing a full wetsuit in an indoor pool for any other reason than fitting purposes is absolutely a strange denizen, and quite possibly the biggest Tri dweeb/geek on the planet.
Now sometimes in the early summer in the outdoor pool for cold early morning swim workouts wetsuits are permissable. Chlorine is not so good for them though.