THE SMART TRICK OF DAN WESSON COMPENSATOR THAT NO ONE IS DISCUSSING

I observed in a collector's book the other day a listing that said the model twelve was manufactured only in 1970 and 1971--a discrepancy needless to say. I am thinking we however do not have fully exact and dependable information on Dan Wesson generation.Furthermore, it has a 2 line roll marked shroud likewise. I know they transitioned to one line