I have encountered many wonderful things here in Mexico, but these taps are not among them.
After nearly a week, I still have no idea which I am supposed to turn them to achieve the desired effect — or any effect, come to that.
The tap below, on the other hand, is a revelation. You learn to press the little lever *just so*, and get just the water you need, with no waste, no scalding, and no stress.
Thank you Mr or Ms Mexican tap designer for this breakthrough.