Robert -
When are you available to instruct myself and others on "proper" fishing methods? A rhetoric question as I'm sure that your comment doesn't come across as you intented.
Over a lifetime of fishing (both gear and flies) and more than a few fish caught I would say that occassionaly foul hooking a fish is inevidentable.

I remember a summer steelhead that missed my waking fly, completely clearing of the water and landed on my fly which ended up hooked in the pectoral fin - even though I never even set the hook I ended up with a foul hooked fish on a surface fly. Coho in the river are notorious for ending up fouled hooked. Many times I have watched fair hooked fish roll up the leader, the hook fall out (barbless) and as the leader unwinds the hook ends up in a fin or elsewhere - another foul hooked fish. Chums are another problem - In the fall and early winter I have gone to trying to fish several feet off the bottom with my wet flies and still foul hook chums way more often than I would like. Given the forecast for chum returns in the Puget Sound area I would say that it would be likely that in a week of fishing in late November or early December with swung flies, drift gear and bait, plain yarn, spoons or other terminal gear it would be highly probable that any angler will have one or more chums fouled hook when brought to hand.

Eliminating corkies and other floating terminal would help reduced the flossing problem though there are many that are quite adept at this method using bait or yarn. Lots of intentional snagging occurrs with lures, jigs, and even flies. On the North Fork Stillaguamish (fly only water) there is a annual problem of folks (I refuse to call then anglers) snagging salmon using weight flies.

While we can and should continue to regulate fisheries to help to control this distasteful problem the underlying problem continues to be the erosion of our collective angler ethics. It is becoming more and more common for "fair chase" ethics to go out the window in favor of ego boosting success. The ultimate solution is ourselves not some magic "rule".

Tight lines
Smalma