I'm with my buddy High on this, too.  If I'm sketchy about a particular route, watching someone style it first gives me a good visual model for my own efforts to send it(even though I may fall far short.)  Unfortunately, being open to this external influence has also worked against me, as I find it hard to style a route after I've just watched someone panic and flail.  Can be a little hard to shake the bad vibes.   
  
Still, watching someone climb beautifully, or do anything beautifully, for that matter, is inspiring.