Mahirap maalis ang coating oras na nilagay sa windshield. I also experience shuddering wiper blades. So for me I just keep the windshield clear and clean as much as I can and just drive slowly if it's really bad, or park by the side of the road until the rain dies out. No point in risking it if you can't see outside.

To remove the coating I suggest using a clay bar. I've heard that vinegar (diluted) also can clean the windshield effectively with newspaper. A good polymer-based wax (long lasting, compared to carnauba wax) could also have the same effect as the Rain X or other brand repellants.