Why is the Teague system such "rocket science" when every corner gunsmith and some not neccesarily located on corners can enlarge a shotgun bore to specified dimensions? Briley does other types of insert tube. Why can't they do the Teague style? I suspect Briley is just too busy with other projects and has the Teague system on the back burner. I don't object to Teague having a monopoly on this method, I just can't figure out why.