First off the chart is showing water only, no one runs water in the winter time. Now if it works the same with anti-freeze and allows the engine to warm up faster that's fine, but the chart shows it lowering the water temp 20*F. While the engine might warm up faster according to the site, the water is 20* cooler on their chart which would translate to less heat coming out of the heater once the engine is warmed up. That means less effective heat and defrost in the winter which could be dangerous.
Unless I'm reading to much into it I'd rather have my coolant hotter in the winter and get more heat in the cabin. Hotter coolant could also translate to the oil being a bit hotter too, not in direct proportion but still a little hotter, which is another thing I'd want in the winter. Hotter oil gets moisture out faster, and will reduce sludge. Blocking off a small section of the radiator is cheaper and more effective in warming up an engine faster in the winter. In the winter I'm looking for all the heat I can get. JMO
IMO good fill of mfg spec'd anti freeze and distilled water is all an engine needs, then follow the mfg recommendations for replacement.