Well, since you asked... I think blaming McQuery is no better than blaming Joe. Just because someone is 6' 5" doesn't make them perceptive to what may be going on or trigger him to spring into action amidst the confusion. While McQuery hasn't been the most consistant witness and maybe could have stopped Sandusky on that same day, it's possible that the same failures/bad decisions within the child welfare/police groups could have take place even if McQuerry called 911 that night.
If there is one truth to come out of this whole mess is that Penn State (players, coaches, & admin) and America as a whole was terribly naive about child predators, how to spot them, and who is to blame.Everyone wants someone to blame beyond Sandusky. Penn Staters blame McQuerry, TSM, BOT, Corbett, etc. People outside the Penn State community blame Joe, Curley, Spanier, and Penn State football. Who knows how much tangential blame each of these persons or groups deserve. Most are not as guilty as others want them to be, but this doesn't satisfy our desire for placing blame. I'm no psychologist, but maybe it's because we are afraid that we could have been in their shoes (not Sandusky's) and their must have been something wrong with them because we would never have let this happen.