I blanket, not really because it gets cold (rarely under 45 F) but because it rains. A lot. And when it rains hard here, 90% of the time it is accompanied by 10 MPH wind.. Wind usually is what does it, combined with rain, as it blows up a horses furry winter coat and the rain can therefore get inside the horses coat behind the "guard hairs."
I also think this is almost exactly like the shod or barefoot horse .. It changes on where you live, and also on your horse and its living conditions.
“Good things come to those who wait… greater things come to those who get off their ass and do anything to make it happen.” - Unknown