Everyone is entitled to their own headcanon. Steven Brust once wrote this:
The Cool Stuff Theory of Literature is as follows: All literature consists of whatever the writer thinks is cool. The reader will like the book to the degree that he agrees with the writer about what's cool. And that works all the way from the external trappings to the level of metaphor, subtext, and the way one uses words.
For tiefanatic, Traviss' Mandalorians aren't just cool but the coolest. That would be okay, except that any time it becomes clear that his headcanon is in conflict with either the established canon or someone else's headcanon, tiefanatic goes to war.
And, to be perfectly honest, I kind of have to respect his dedication to this particular lost cause. It's just that sometimes it's too much fun to poke at someone else's cognitive dissonance.