They aren't all desperation throws.  If A. Robinson is in single coverage - it's part of the game plan to give him a chance at a 50/50 ball.  If you watch any of the pressers - Blake, Olson and Bradley have all stated this multiple times. 

 

Still - while Blake is pretty good under pressure compared to many young QBs, he does let if fly a few too many times in those situations. He will likely get more savvy about throwing some of those out of bounds as he matures and the line improves. 

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