I'm curious as to why his career ended after only 10 years. I remember a series of 30ish and 20ish goal seasons with the Flames. Legends of hockey write-up doesn't say much. Was it injury problems? Did his production drop after Lysiak was traded to the Black Hawks? Any other reason?
He did suffer some injuries, but I don't think that they directly caused an early retirement. They did perhaps lead to his fairly rapid drop in production.
He did play one year in the AHL after his last NHL season.
Calgary had a rough start to the 1981 season and had placed Vail on waivers prior to making the trade. Near the same time he was traded to Detroit, the Flames also made the Mel Bridgman-Brad Marsh deal with the Flyers. Because of that, I recall reading that Vail and Calgary's coach Al MacNeil had a personality conflict. He didn't last too long with Detroit before being sent to the AHL. He did end up in the Kings' 1983 preseason camp but I'm not sure if he was released at that point.
Under Vail's entry in the book Players it's mentioned that he liked partying and the nightlife a little more than he should have, and that lack of self-discipline was a reason why he only had a good career instead of the great career he appeared headed for after his big rookie season.
Al MacNeil said when Calgary traded him that while Vail was well-liked by his teammates, his performance on the ice was too often "lackadaisical".