If it sounds horrible, it's because your interpretation of it is horrible, also horribly wrong. Iodine doesn't matter, but such salt is almost always coupled with numerous other additives that can be quite harmful to the teeth, e.g. starches, sugars, etc. It is best to get pure salt.
If not having an active infection, it needs to be done only at night before bed. It is not a big deal if you don't eat or drink anything after it. Do not swallow it while you rinse it. The moment you drink something after it, that's when it becomes horrible.
If having an infection, it is better to do it at least three times a day while you're waiting for professional treatment, e.g. antibiotics and/or a root canal.
If not having an active infection, it needs to be done only at night before bed. It is not a big deal if you don't eat or drink anything after it. Do not swallow it while you rinse it. The moment you drink something after it, that's when it becomes horrible.
If having an infection, it is better to do it at least three times a day while you're waiting for professional treatment, e.g. antibiotics and/or a root canal.