JFruser- I think you are spot on with your analysis.
. I do suspect that many American bishops were covering, big-time, for priests under their authority. If the information does not get to Rome, Rome has less to act on. Why the bishops' cover-ups? Blackmail. Bishops who had earlier been though the aforementioned whacked-out seminaries had skeletons of their own in their closets. When one of their younger priests took advantage of a young boy and was found out by a bishop who did not indulge in pedophilia, but did indulge in adult homosexual activity, what is that bisop to do if Father NAMBLA theatens to expose Bishop Negligent? Rather than risk their own position, Father NAMBLA gets switched to another parish or duty and their victims are sacrificed for their ecclesiastical careers.
The Milwaukee Diocees had a former Bishop that was forced to resign after if was found out that he was taking hundreds of thousands of $$$s from his diocees and using it as hush money to pay off another man he had a fling with in the seminary. This Bishop was corrupt on many other levels, most of which he was defiantly at odds with the Pope.
http://www.culturewars.com/2002/Weakland.html
http://www.seattlecatholic.com/article_20020607_Archbishop_Weaklands_Legacy.html