I am not sure what is in Water Wetter or Motor Max, but I suspect what they are is wetting agents which reduce surface tension and reduce bubble formation. The molecular structure of water is such that on a microscopic, or submicroscopic level, the forces which maintain bubble film strength are surprisingly formidable. (I am not a chemist, please don't rip my head off on this stuff) Wetting agents, by reducing surface tension, allow water to wet adjacent surfaces better, thereby maximizing heat transfer into the water stream, and thereby carrying more heat away from the metal parts to the cooling system.
A while back I posted an enquiry wondering whether anyone had tried Evans NPG, which is neopentyl glycol, as a waterless coolant. If anyone has, I would be interested to know- water, as you know, has its' problems in cooling systems, it rusts things, and it would be nice to find a way to do without it.