Because the lifeguard is wearing a sailor hat, and has Bluto's voice and physique, it is logical to assume he was originally intended to have been Bluto before someone decided to use a new character instead.
The placards seen early on are a nod to the advertising campaign of Burma Shave brush-less shave cream. Popular at the time, the company placed signs intermittently along well traveled
roadways that would spell out a jingle for the shaving product.
The swan and jack knife dives are depicted here and were considered quite artistic at the time.