Yeah, I've always said that WFR helps you understand *exactly* how scared you should be when someone gets sick or injured! You still can't do much in the field, but at least you know whether you should be concerned, worried, scared or terrified!
That said, it does help you recognize problems earlier and there ARE some life or limb saving interventions that you can apply.
To take one example, shortly after my first WFR course, my partner failed to self-arrest following an involuntary glissade and cracked some ribs. WFR allowed me to diagnose the situation, exclude more serious stuff, and I knew what to watch out for as we self-evac'ed. Without it, we probably a) would have been scared spit-less and b) called for a rescue.