[St.Chuck]

I will grant it seems authoritative to the layman-

I think you downplay the significance of the motu proprio. Traditionalists will adhere strictly to Pius X's motu proprio concerning sacred music, but ignore completely JPII's Ecclesia Dei. This is another example of the cafeteria catholicism I have pointed out in times past.

[ultima ratio]

Pius X was not in conflict with his own papal legal system. Dei Ecclesia Adflicta, on the other hand, contradicts Canon Law--and it is the latter, after all, which determined the actual status of the Archbishop. Unfortunately, for those who hate the SSPX, the canons grant exceptions to penalties and the penalties themselves, including latae sententiae excommunication, are dependent for their validity upon the conscience of the subordinate in an act of disobeying a superior, including the Pontiff. It states explicitly that in a state of necessity, the subordinate incurs no penalty if he disobeys. Even if the individual only wrongly believed this--and Archbishop Lefebvre had no doubt this was the case--then he incurred no penalty. This is simply the law, and it is papal law, whether the Pope latter mischaracterized the situation in a letter or not. You, like a lot of others on this site, wrongly believe the letter itself had excommunicated Lefebvre. But it most certainly did not. Had the Pope wanted to personally excommunicate the Archbishop, he would have used the alternative method--i.e., he would have called a tribunal. This he did not do.