In reply to Slackboot:
Watched Johnny Dawes cruise up Technical Master (f6B) in his Reebok(?) trainers in Stone Monkey - several years later I was thrashing around at the foot of it wondering how to even get off the ground.
As Denzel says, it's lots and lots of training and practice (plus natural talent/potential).
I often think similar when watching a good guitarist, they make it seem so smooth and calm, almost as if it's in slow-motion sometimes. I guess the difference with playing guitar is that you can usually make quite a bit of progress towards your goal whereas with climbing, no matter how much training, you are limited by your body-type, physiology etc.