answer:Possibly they rarely do that type of work. It’s body work. Also, I think there is always a reluctance to remove windshields and rear windows if there is nothing wrong, but if the seel needs fixing then something needs to be done. There probably always is a risk if they fool with it, you might wind up needing a new one. It’s glass, it can break. My Porsche mechanic actually once told he doesn’t get the “Chinese” glass, because he feels they are weaker. I don’t know if he gets the glass American made, or somewhere else. He works on our race car, so the safety of the glass is even more important. He had a bad experience on the track with the Chinese glass. However, people are on the track in cars from the 70’s and 80’s all the time with orginal glass, so I doubt it weakens. I really don’t know for sure though. I know one time I had a Coke bottle just come apart, and I don’t know if the glass had weakened over time, or if it was a bad bottle to begin with. Hopefully, a science minded person who knows about glass can answer your question.