"The “Rad Traddies” have a whole range of causes and beliefs ranging from sedevacantism to enthusiasm for traditional devotions, right-wing causes and the traditional Latin Mass."
The issue, of course, is not with his comment about sedevacantists, but rather that it would appear that even simple enthusiasm for "traditional devotions" and "the traditional Latin Mass" is being defined as beyond the pale.
Having spoken with Fr. Longenecker in the past, I questioned to myself whether this is what he actually meant, or if it simply was "lost in translation" if you will. I determined to ask him about it.
He confirmed to the NLM that it was never his intention to make such a suggestion:
No, I am not against the Latin Mass, but against the extreme traditionalists who rubbish Vatican II, support cranky right wing conspiracy theories and take a sedevacantist or semi-sedevacantist position. That's why I referred to them as 'Rad Traddies' ...
Those who support and encourage the Latin Mass within the full life of the church as promoted and permitted by the Church I have no problem with.
Returning to Father's definition then, his intent was to group the characteristics of what constitutes a "radtrad" together as a package, and not rather to suggest that each individual characteristic was in and of itself problematic. Indeed, as Father noted to me, "enthusiasm for traditional devotions... and the traditional Latin Mass", when done in the context of the bosom of the Church, is a good and Catholic thing.