Doug,
I think it has to do alot with your location in relation to where the fish are headed, for example, I've spent 11 years at 2 resorts that target different runs of fish, the first, near Ketchikan, has alot of fish returning to local hatcheries and watershed and while there were a number of wide open bites with fast and furious action, there were also alot of times when you would mark fish after fish with not so much as a sniff. These fish were close to home and at times, just weren't interested in eating know matter what we threw at them.
The second resort, near Craig, which, other than a small run of silvers to the Klawock river, was mainly an ocean fishery for migrating fish that still had alot of traveling to do, these fish are generally very agressive and easy to catch, lockjaw is not a term you here much in this area. As I mentioned, there is the 1 small local run that I have fished alot and have witnessed wide open bites come to a screeching halt while there are still alot of fish showing on the screen.
I think the same principles hold true here, the fish on the coast and straits still have some miles to cover therefore they have to eat, and generally more agressive, once they hit P.S. there almost home and I don't think feeding is as high on their priority list.
I could be totally off base here (wouldn't be the first time) but just what I've experienced and the conclusion I've drawn from that experience.
1 last note, just talked to some buddies of mine from the resort I worked at 2 years ago and they informed me, this past season was the worst silver season they have had in 12-14 yrs. up there, runs here may either be late or may not be coming at all, getting kinda late.