So far it looks like there is not much difference than what I do in this climate, except for the metal blades. I have never heard of that and would never consider using metal of any grade to scrape glass.
It doesn't happen here often, but on the rare occasion I need to scrape auto glass, there is usually considerable ice build-up. From watching other people screw up, I have experienced the following:
- Don't use hot water over ice, the sudden temperature change will crack the windshield. And depending on the wind conditions, the hot water can refreeze on the window compounding the problem.
- Don't use the defroster blower to melt ice, the same thing can happen. The hot air blowing on the lower part while ice is still stuck to the upper part will crack the windshield.
- Don't run the wipers until the windshield is completely clear. I have a friend that didn't believe me on this one and was too lazy to scrape the whole windshield. He made a hole that he could see well enough to get to work and used the defroster and wipers to make it bigger. His wipers fell apart and scratched the windshield.
This doesn't apply to happy fluffy snow, only to hard frozen sheet ice like we get here sometimes.