Sammy Hagar was only in the music business for a good time whenever he made a record. No one could have expected that he would have become one of the biggest rock stars on the planet when he was working with Montrose, but even for a kid who had barely entered his 20s at that point, he was already the kind of seasoned veteran that any other rock and roll frontman wished that they could be. That kind of innate talent only comes from people who are…