Have to say this thread has some interesting info.
Never thought about what might happen if it was -20 and the heated fluid hit the windshield

I've never used my heated washer fluid while driving. Only use it when first getting into the vehicle to melt the ice off.
Also, I break the wipers free first, if they're frozen solid, since they swipe automatically once the fluid is heated.
The first sprays come out without the wipers moving but doesn't mean that will unfreeze the wipers enough for them to move when they make the first swipe.
