With that said, I don't think this is a fair comment. You use NSW from the ocean so of course you have no reason to test, you already know your waters fine. It's kind of like cheating.
LOL, it would seem so but it's not. (I actually do test 3 or 4 times a year)
I have been using NSW now for almost 5 years because I live near the sea but for the first 45 years, I used mostly ASW like everyone else. I also collected all my rock SCUBA diving but I had to bleach it before I carried it home on my lap on the plane, so it was dead. I also change very little water, only 20% about 4 times a year so the parameters are not close to anything.
NSW from New York is severely lacking in almost everything including salt as it is usually very weak and I have to add ASW to it.
I helped start I think 4 LFSs here in the 70s using ASW and dry rock so I do have experience doing that.
Besides that, it is experience that allows you to go for a long period of not testing because I can tell by the corals and fish what needs to be done, if anything.
I believe the tanks that are tested and tweeked the most are the ones with the most problems. There is no parameter that has to be exactly "anything". Close is good enough as the parameters fluctuate throughout the day so if we add or remove something we screw it up and drive ourselves crazy.
The corals we keep don't hardly use all the calcium, alk, iodine, magnesium and other stuff we add so often.
Just my opinion of course but thank you for keeping me on my toes. At my age, it ain't easy.
