If you had smoke silver paint with the cracked clear coat you would know the value of applying a silicone based product to the paint. Is it a radical, unorthadox use for this product? ....yes Is it effective?.... absoluitly.
BTW when the paints is as damaged as mine is everything has to be stripped before a respray anyway.
I don't know where you are located but I found an amazing body shop in Los Angeles. He did collision repairs on my 2000 Range Rover and quoted me $2200 to repaint the 420.