True. Good arm is optimal, but hand transfer and footwork can only be developed if athlete has quickness. Without quick footwork and hand transfer, good arm still will not get it there under 2.0 (unless absolutely perfect pitch).
I've seen catchers improve with certain drills, but that "pudge-like" quickness is natural. I've seen many "good armed" catchers slow themselves down alot by "square up" to throw, gets there but not in time. So what is the value in good arm there? With the criteria given, I'd take the "blocker" over good arm.
But, as we all know, the "whole package" is optimal. Yes, some catching skills can be developed, but quickness is often overlooked as a catching "tool". JMHO