I don’t think I could ever get by with just water, my beard is too wiry. LSL, blond hair can be finer–you think that’s why it works for you?
An issue with these new multi-blade shavers is that they clog easily and that makes shaving harder/less close/more likely to cut. You’ve got to rinse (or I do) between every few strokes to do a good job, especially if you’re using a relatively thick/foamy shave cream.
I can see that if you were used to using a thicker cream and then used something like mouthwash, which I presume does soften the hairs somewhat while clogging the blades less, it might seem like an improvement.
Agree that you’re on to something here. Once the gaps between a multi-blade razor get clogged with hair/soap sludge they pretty well stop cutting. Keeping the gaps clear improves the shave a bunch.
what you want is lubricant for the skin. Also WATER to soften the hairs (as it does for cotton, wool, and other natural fibres), and SOAP to wash the oil off the hair (which is there to protect the natural fibre from water). Possibly ALCOHOL may work as well or better than soap to clean off the oils and allow the water to penetrate the natural fibres.