doesn't this all come down to learning/gaining some knowledge as much as using your brain??
it's all well and good to be spouting off about "using your brain" but if you don't know what to look for how would you know that you're about to fuck up?
in this accident it sounds like it might've been pretty obvious but that's not always the case.
i've told the story many times of encountering some gym climbers in trouble at smiffy. DH had to "rescue" one of them. They came complete with a crossloaded carabiners on the edge of cliff for their anchor, no knowledge of a prussik or any other useful knot, and limited knowledge of their belay device. They just didn't know what to do. Some of it seemed really obvious to me but it probably wasn't if no one had taught them.
Unfortunately, some of the learning process involves going out and doing it. Hopefully people find knowledgable mentors. Lets face it, we've all been lucky at least once and their isn't always someone their who knows. Everyone talks about needing to push themselves in order to get better. Well for some folks pushing themselves involves going outside.
There's a lot to learn but it comes down to more than just "using your brain". Hell i'm so tired half the time my brain doesn't work that well.