CM when did CWT's come into being? It was when the Canadians started recovering the tags that they figured out how to target US stocks AND DID.

SBD your off beam about 2/3'rds. Hatcheries were built to make up for ( mitigate ) lost natural production from human activity and provide for additional harvest. The ocean harvest is a fishery well after hatcheries came into being and took off like crazy with the growth in ocean sport fishing.

Through the history of harvest most was terminal based but not necessarily net. Traps and fish wheels dominated for many years. It is in my life time that the mixed stock ocean sport & commercial fisheries really developed and frankly they have had the most detrimental impact of any harvest method utilized in the PNW. It is the word mixed stock that is the key.