Mike, I can't speak to 'lake run' Salmon, but given the original stocks came from my corner of the world .... some do some don't depending upon which run the 'eggs' were taken from.
As an example we have two (well three) major runs of King Salmon (the other being a late September/October run of Coho) and the 'Spring Kings'? Only by 'dumb luck,' 95% are probably 'Flossed' whether by Gear Guys or us fluff chuckers.
Should note that the vast majority of these fish come out of a Hatchery on the upper Rogue, so why they chose this run (for eggs, etc.,) is a bit beyond me.
Ahhhh, the Fall Kings ... even 100 miles up river they'll take the same fly patterns as summer run Steelhead. Just a question of where you're on the river to 'legally' fish for same. But when you're chasing/casting for a 3-5 pound fish and you hook into something 30 to 30+ ..... it's a OOOOOOOOH Boy!.
SW Oregon Rivers have (in the main) quite healthy runs of October/November (even into December as you move further up the Coast) and the closer to 'The Salt' you are the higher the probability you'll take Salmon on the fly.
Look up the Chetco River (the Morrison Hole about 1.5 miles up from the river mouth) and you'll find 'combat fishing' at its "best."
Had to laugh as I putted through the latest issue of Fly Fisherman magazine; the last article was about fishing the Chetco's fall run. Only 'error' is the Author calls it "Tide Rock," not true, that's another half mile up river. It's Morrison; but who cares? The rest is dead on.