Fortunately, the odds of encountering a man-sized or larger octopus or squid while swimming is pretty small, and I do not know how aggressive they are. The documented record for an octopus is about 156 pounds, though there was an anecdotal story of a 600 pound specimen (unproven). But most are fairly small. As far as Squid are concerned, most are about 24 inches long, so are hardly a threat to the average swimmer. Larger ones, of course, exist, and I would certainly never want to tangle with one (apparently some have hooks on their suckers). That said, the odds of encountering one at your local beach would be so unlikely that I'd think that a fear of being hit by a 1987 Cadillac while taking a dip on a beach in Tahiti would be a lot more rational.
I think you are vastly underestimating the sheer strength of those things. Size matters very little when an octopus the size of a puppy can squeeze you hard enough to break every rib in a second. Squid are less of a threat in my never humble opinion, but that is because they are not as interested in you. If you manage to attract the attention of a large squid you are pretty well screwed anyway, but I cannot fathom what you would have to do. Octopods are territorial though. I saw a video of an octopus the size of my cat killing a shark easily twice my size in seconds. It just grabbed it and crushed the life out of it and swam away like it was nothing.
Animal to eat: Chickin Animal to not eat: Also chickin. Color: Chickin. Maybe I'll do this again after dinner.
"I eat more chicken Than any man ever seen" Anyone who gets the reference has gotta be nearly my age (hint -- it goes back a few decades).
[<-]I'm sure there are some younger fans of the Doors out there who would have been introduced to it through that cover.
(Does this count as necroing?) The doors are awesome. Also: Animal: Cats, Raccoons Colors: Blue or brown or whatever I feel like that day