I am assuming that you are fishing for salmon w/k15's. If you are fishing in a kill fishery I would stick w/the trebles but I change the factory trebles to 2/0 on 15's #384 Eagle Claws. They are soft but I would rather replace the hook than loose the fish.If you are in release area use 3/0 Gamakatsu siwash. I turn the back screw eye 1/4 turn and put single hook on the split ring w/point pointing up. I also put on a #7 barrel swivel on the front hook w/3/0 siwash. I would never use a siwash unless the regulations make you.
Another thing is to really wait when a fish is taking and load the rod then hitum' a good one.