We had a member here who got water in his Sub, he knew it right after he got out of the water, and it took a few days to get it to the watchmaker- we saw the pics- man does rust happen fast! Not to mention lume is like a sponge and that lovely dial will lose its lacquer faster than you can blink.
I know we have some serious dare-devils here who like to drink milk a day or two after the expiration, who pass on the right, and some who will even bicycle without a helmet!
But water is what Seiko’s were made for- just keep the speedy on dry land- some risks are just not worth it.