Works for me. Headaches without. I often wake up a few times each night to drink water to get rid of dehydration headaches. And I carry water with me all the time, thirst all day, headaches when it runs out. (like yesterday). Worse in the desert.
One guy I worked with suffers from extreme debilitating migraines and only drinks about 1/4 of the amount of liquids that I find necessary to avoid headaches. (which is about ~3-4 litres/day). I would tell him if I did the same I'd have major headaches too. But no, he doesn't want to hear it, says water doesn't work. Too dumb perhaps.
Actually I can feel a slight headache now so will go drink some more water to get rid if it. If it hurt more I'd reach for 400mg of ibuprofen or two and, of course, more water.
Someone finds out you suffer migraines, “oh drink some water!”
Also chronic conditions tend to have cycles of weeks to months.
People get tired of dealing with you much faster. So you learn to hide your symptoms as best possible.