Consider the following:
A football playbook is, apparently, a volume of some complexity. (Non-sports fans, please refrain from snickering -- no, of course it's not as complex as, say, your average calculus text, but when was the last time you had to integrate a function while a metric ton worth of linemen were barreling at you?). Somewhat analagous to choreography, it (the playbook) requires the players to memorize and know by name a variety of plays, which describe actions including who needs to be where when such that the ball can most effectively be transmitted (by them) into the opposing end zone for a touchdown.
Recall now the 1985 Chicago Bears, coached by Mike Ditka. In addition to making effective use of the talents of Walter Payton, somewhere along the line, Ditka got the idea of giving the ball to the biggest guy on the field, William "The Refrigerator" Perry. For doing what everyone who has ever touched a football knows, Ditka was lauded as a genius.
They won the SuperBowl.
So, next time you have a block in your writing, whether writers' block or you can't quite figure out a logic problem in your plot, do what Ditka did. Go back to basics. Consider the obvious.