One of the items listed was about carrying your fins into the water on a shore dive. when i started you always wore your fins into the water and "WALKED BACKWARDS TO PREVENT TRIPPING". The BCD sure changed the need for that practice. Of course there were rules about the J valve also. As opposed to a k valve the j valve will give you air when you get low.
So many technologies have changed and what were once good rules are now moot and have become todays myths.
So many technologies have changed and what were once good rules are now moot and have become todays myths.