scubaozy
Contributor
Most of us make first cesa at the moment we are born, does that guarantee you will make an safe ascentDeploying a pony involves reaching down grabbing something and putting it in your mouth, a skill most have acquired before the age of one. Many recreational divers rent their tanks at the dive location and doubles and H-valves are not normally available unless the shop caters to tech divers. Even if you have your own they may not be easy to travel with depending on mode of transportation. If the chances of having sudden gas loss is so rare why do we teach buddy breathing or even dive with buddies at all. Not everybody travels to warm waters to dive, my last four dives trips that were not local were Greenland together with Labrador and Newfoundland, Victoria Island, Newfoundland and then again to Victoria Island. A lot of people also travel to the Great Lakes for the fantastic diving available there.
Please remember the title of this thread is not Should everybody use a pony tank but is Recreational pony bottles, completely unnecessary, why or why not. In some situations my vote is for Piece Of Necessary Emergency Equipment. (PONEE)

If you can find only basic equipment in a certain location, probably locals see it fit to dive with that equipment there.
Let me summarize how different people see the world with a little humor.
American: I need my weapon because world is an evil place, things go wrong, I want to feel safe.
Greenlander: I need my weapon to feed my family and protect them from wild animals.
European: I do not need a weapon because I trust others to be reasonable and statically I will not be safer if I had one.