No wonder there are hardly any excommunications in the Novus Ordo sect:
http://www.vatican.va/archive/ENG1104/__P4W.HTM

I looked up the 1917 translation by Ed Peters, which cross-references to the 1983 Code, and all these myriads of exceptions to excommunication do not seem to be there.

Many Novus Ordites consider Abp. Thuc "insane," yet ¿why wasn't 1983 Canon 1322 applied to his "excommunications:"

Can. 1322 Those who habitually lack the use of reason are considered to be incapable of a delict, even if they violated a law or precept while seemingly sane.

¿Why wasn't this canon applied to Abp. Lefebvre:

Can. 1323The following are not subject to a penalty when they have violated a law or precept:
 …
 4/ a person who acted coerced by grave fear, even if only relatively grave, or due to necessity or grave inconvenience unless the act is intrinsically evil or tends to the harm of souls;

or at least the severity of his punishment diminished according to:

Can. 1324 §1. The perpetrator of a violation is not exempt from a penalty, but the penalty established by law or precept must be tempered or a penance employed in its place if the delict was committed:
 …
5/ by a person who was coerced by grave fear, even if only relatively grave, or due to necessity or grave inconvenience if the delict is intrinsically evil or tends to the harm of souls;

(Perhaps because the Modernists thought his support of Tradition "tends to the harm of souls"!)
 
The whole concept of exceptions even to latæ sententiæ excommunications seems strange to me. I thought latæ sententiæ excommunications were excommunications by the very act itself, not by the Church as in ferendæ sententiæ excommunications.