User blog comment:Xilinoc/Ch. 670 - The Perfect Crimson/@comment-24574959-20160414230229/@comment-26091912-20160416005957

"Pernida was hard to defeat due to its ability to evolve and make clones of itself from severed "body" parts. Askin was incredibly difficult to kill and had a very effective Schrift power. Gerard seems kinda equally difficult to kill (for the time being) because of The Miracle."

That's precisely it. They're "elite" not because of their fighting skill, battle strategies, or intellect, no. Instead they're "elite" because they're, as you put it, hard to kill. At least most of the other Sternritter had to to put skills to use. Whereas these guys require no skill at all; they just got lucky.