I do have to say, though, that you're the one guy who's come up with a reasonable reason for suspicion -- i.e., he should have known better. If the guy has lived on the Oregon coast for only ten years or so, then ... he might not have known better.
Raise that to probably wouldn't have known better. A lot of people you'd think should know better understimate the ocean. I've seen it a lot -- you have too, right?