Salty lemon water? Why would that be lavaging? Perhaps if the concentration is extreme. Otherwise I doubt it would have more of that effect than coffee.
I dunno about this. Many medical professionals encourage heart and high blood pressure patient to drastically limit salt intake because salt causes you to retain water.
What does this mixture of himalayan salt and lemon do that causes the diuretic effect?
I don't think that there is disagreement on the existence of healthy routines. But we should be skeptical of the benefit of "Himalayan salt" and equivalents. Have you tried switching the salt to just common salt in a blind experiment? Have you tried only lemon water? Himalayan salt is a luxury, and there is not particular reason to believe that it does anything more than a placebo.
I drink just water in the morning and I am out to empty my bowels right after. I don't think that has much to do with Himalayan salt.