Seacat, I think your assessment is right on the money.
I, for one, believe you would hear alot more about the presence of these large BM , as uncommon as they are, if more people fished for BM. Today, with regs and other fishing opportunities available, that just isn't going to happen. I think even Mr. Nelson would have to agree. 20-30 years ago when people stayed closer to home to fish and seasons were wide open you heard and saw more of these fish. They were often referred to "springs" and folks believed they migrated in (and out) with the large winter squid populations. They were generally found in the mid sound areas in deeper waters (JfHd, MidCh, NoPt, AllenB ,etc.) but my fishing mentors always said to be ready cause you never knew when one would pop up. Last year, I was fortunate enough to have C&R a similar size BM that I caught in a closed to salmon area (Klaus Rocks) in January in only 40 ft of water in the bright midday sunshine while puttering around with a friend. I got a pic somewhere in this dump. I have also taken them near Pt Monroe, Jeff Head and the Agate Pass area over the years (we're going back now).
But, then again I've also wondered if these fish could be late maturing local BM too. Just as there there are precocious jacks in salmon populations that return a year early, why couldn't there also be a few late maturing (1 year later) adults in the population. Especially since many Puget Sound hatchery chinook are released later by design to promote local habitation. If they are still doing such a practice. Any fish biologist know what the drill is with the hatchery BM program these days?
Anyway, one thing is sure, although these hogs are few and far between (just like 20+ Steelhead), they are definately out there. And with all due respect to a hard charging spring chinook or mamouth ocean king, I still believe BM, small or large, pound for pound may be the spunkiest fighting salmon around. Anybody else agree or disagree? See you off Apple Tree.