As usual, you're having way too much fun.
Even though, most months of the year, the South Side water temps are in that 82° range, there are some other things to consider, most especially at CocoView. hdtran might be getting 4 dives a day plus night dive. (quite likely, too!)
The way your body recovers between dives during the SI (surface interval) is a big factor, especially with being u/w for 5+ hours each day. Other factors include the weather (rainy or sunny?) and a very difficult one to perceive... how stable are the boats? If the boats are pitching about, your body is constantly adjusting and working, versus resting and recovering. CCV's boats are designed to ride out the waves (versus going fast under power).
Most first timers at CCV that have this temperature/insulation question are thrown a real curve with the heavy dive numbers that they can access. Repetitive dive schedules of this intensity are new to most and generally unavailable unless on a very few liveaboard boats.
Due to their shallow and extensive near-shore dive sites, ones with relatively less water exchange than that of the North/West sides, the water temps along the South are affected and increased more by the direct Sunlight exposure. You will usually find water temps 1 to 2 degrees higher on the South side, a factor which I see as absolutely insignificant, but something that many find of critical import. Once you know that it's in the low 80's, I also see very little difference between "surface" and "depth" readings, another number to which many attach great interest.
When you crack open the Encyclopedia and look up warm water pretty fish ® diving, there's a picture of CocoView, likely with hdtran doing a shore dive.