As glenp pointed out, if you've time to think through how your going to react in the crash you've probably got time to sort it out and avoid the crash. Half the crashes you see with beginners tend to be in situations where they're trying to bail out (riding a difficult section with one foot scooting allong the ground for eg) and as a result tend to mess up.
Most of the big bail outs you see on videos tend to be off jumps, which are easy (relatively) to bail on as you just kick the bike away and try and land on your feet taking most of the energy before sliding downt he transition.
I'm no saint and do have plenty of bad habits, but an easy one to get out of was thinking about crashing, simply swapped to flats, and voilla, no need to ride difficult sections constantly planning how I wass going to get off the bike if I had to. I can now ride the same sections just as quick on spd's but after theyve failed me once they still give me the heebie jebies soemtimes.