Concerning the passenger's pool activities...
I had always thought that the pool, as it was part of the fancy bath complex on F-deck, was also part of the "Turkish Bath Experience." A person would spend some time lounging around the Turkish Baths, essentially a sauna from what I understand, hang around the cooling room a bit, then hop in the pool to get the sweat off, finally washing the salt off in the showers.
This is upheld a little by Mrs. Speddon's statement:
"I took a Turkish Bath this morning. It was my first and will be my last, I hope, for I never disliked anything in my life so before, though I enjoyed the final plunge in the pool."
Seems the novelty isn't all it's cracked up to be.
This is just my interpretation, mind you. I may be way off.
Though it would be interesting to see personalities such as Astor and Widener stumbling around the pool going "Marco!" "Polo!"
Josh.