An alienator may assume that if a parent had been physically abusive with him or her, it follows that the parent will assault the child. This assumption is not always true.
I guess Stuart does not read reports by the American Psychological Association, specifically the report entitled Violence in the Family: Report of the American Psychological Association Presidential Task Force on Violence and the Family written in 1996 which states:
•40 to 60 percent of men who abuse their wife or girlfriend also abuse their children
I don't know about Stuart, but I do not think I would be risking any child with 40-60% odds. Would you?