Hi Eric, i have used the Salt folders everyday on a saltwater kayak for years and I can give you some pretty specific feedback. For me, the main two Salt folders for my use are the Pacifc Salt and the Siren so I will use those two as my examples.
I launch the kayak probably 4 days a week and fish about 6 hours per session. The knives are soaked in saltwater from the time I launch until the time I come in. When I get home I almost never bother to even rinse them with fresh water. Neither knife has ever shown any rust, even after years of this treatment.
I have also done some heavier testing where instead of bringing it in at night, I kept the Pacific salt in a wet and salty compartment on the kayak 24/7. After 2-3 months of that type of storage you will eventually start to see a tiny bit of rust bleed out of the pivot area. Nothing that affected function but it can happen at those extreme levels of exposure. It should be noted that even when this occurred there was still ZERO corrosion anywhere on the edge or the blade itself.
It should also be noted that this only occurs when I stored the pacific salt unused for months in an enclosed and salty compartment. The kayaks are stored outdoors in the tropics and that compartment reaches temperatures well over 100 degrees every day. I’m sure the constant evaporation of the saltwater in that compartment has a much harsher effect than if the knife were simply stored on the open deck. I bet even if you stored one somewhere on the deck of your center console you would never see that. If you hit it for 2 seconds with a hose once or twice a month you’d definitely never see it. Both knives are as close to bullet proof as a folding knife gets.
ETA: The Siren has proven to be every bit as rust proof as my older Pacific Salt. Possibly even more so as I’ve never even observed any of that leakage from the pivot on the Siren. That could be due to the DLC coated pivot on the Siren. I believe they are also doing that on the H1 salts now too so the “almost never“ phenomenon of seeing a spot of corrosion at the pivot might now be a “never” one.