Have you tried just drinking more on a regular basis?

Yes, but since the presence of such pains is the main thing that tells me I've not had enough, it doesn't help too much. An amount that seems sufficient can be easily overwhelmed by say, some hard work and sweating, and/or the use of the car air conditioner to recover from said hard work. Giving a talk or just having a talk with someone can do it, too. So unless I over-drink some of the time, there will always be situations where I end up under-drinking, in the absence of some finer-gauge way to tell my hydration state. I do at least know now to start chugging after I give a workshop, for example. Before I figured out the hydration link, I used to spend many painful hours recovering after each talk I gave.