The Dominicans of Avrille answer the nsspx Fr Simoulin article:
“No practical agreement until there is a doctrinal agreement?” http://www.dominicansavrille.us/answer-to-fr-simoulin-sspx-no-practical-agreement-until-there-is-a-doctrinal-agreement/
I particularly like the comment: “The word ‘sadness‘ (italics added) is repeated five times: appeal to sentiment. But here, it is reason and faith which should guide us.”
Which is of course, what the Domincans are famous for, the use of logic over sentiment.