I have been around the block with this issue several times, but here are my observations:

1) I believe the Kwikfish is hands down the all-time best river salmon fishing lure ever invented. It draws the most vicious strikes an angler is ever likely to witness from four of the five Pacific salmon species. If there is a biter in the bunch, it'll hit a Kwik.

2) Fishing them with stock double trebles SUCKS!
A) Way too many daggers to damage a fish when used in any sort of selective fishery, or when having to sort thru a lot of undesirables to get the fresh fish you want.
B) Although the chances of hooking up are increased, a much higher percentage of hooked fish come off. Why?
a. Any individual tine lacks enough gap to hold a substantial piece of flesh/bone.
b. The fish can use the remaining tines to leverage out the one that stuck the fish.
c. Hook enough fish and eventually you will lose a few when they're being netted.... the points not buried in the fish's mouth have a nasty way of finding the mesh at the critical moment. If the plug gets hung up before the head hits the bottom of the bag, your fish is toast.

3) Fishing them with singles also sucks, but not as bad as trebles. The number of missed strikes on singles is very frustrating, but once hooked a single large siwash is exceedingly unlikely to come unbuttoned, even more so with the new 510 singles. With literally hundreds of strikes under my belt, the running average of landed fish is barely over 50%, regardless of species. That's just the cold harsh reality of fishing Kwiks.

4) Still trying to figure out the best way to rig one solitary single point hook. The only way I have not really tried is with a bead chain off the belly screw-eye. Anybody do it that way routinely? What are your hooking stats.