The terrible thing about free soloing difficult routes that are within one's capacity, is the chance that faced with ultimate danger and need for ultimate self-control, one's nerve might fail and cause an error. That's irony of it - that fear could short-circiut skill, that one would die as a direcy result of being afraid to die.
Royal RobbinsOur ascent, of course, does not end the possibility for new accomplishments on El Capitan. The day will probably come when this climb will be done in five days, perhaps less; and a younger generation will make a new route on the west face.
Royal RobbinsThe rock is a field of battle between our weakness and our strength. We wouldn't touch rock if we were perfectly self-controlled. And he who would climb and live must continuously wage this battle and never let folly win. It's an outrageously demanding proposition. But I never said it was easy.
Royal Robbins