Just my opinion but I would use some care on that. For instance, if the salmon limit is four and I am having a good day I only keep three fish. That way if I get one that is badly hooked or played too hard I can retain it. Now let us say you keep four salmon and continue to fish. Let us say one of the fish is played too hard or bleeding hard from the hook set and is pretty much dead. Now if a C.O. sees you that is not going to cut you any slack, he could say you are one over your limit and write you up a ticket. Just my two cents on the matter.
Bleeders happen, it's too bad but it's all part of the sport.
As far as I know there's nowhere in the regulations where it says you "must" retain a fish because it is bleeding or hooked too bad so I'm kinda thinking what you just posted is redundant and the CO would have to be on glue to right you up for it.
For instance, it would be illegal to keep another fish over your limit {if you had 4 on the rocks already}, you must let it go, dead or alive, crappy but true although and get this, you could STILL commence angling, it's not against the regulations {except for Steelhead as BNF861 has already mentioned}
IMO there's no reason to keep fishing once you have your limit if your intention out there IS to get your limit. If fishing is that good and you want your limit why retain the fish early if you want to fish longer?? The fish will be more fresh if you retain them near the end of your day and you don't have to run into this "problem".
People need to settle down out there and use some common sense instead of going to the flow with a "greed" and "worry about their limit" mentality, it's supposed to be enjoyable, whether you get 10 fish on your line or none.
Beaching everything that gets hooked is just foolish and shows the lack of etiquette in the sport but I guess that's for another topic so......
Like yours, my opinion only.