If it is 50/50 blame on what happens to a team, then the buck still stops with the manager. Wenger actually is a manager that has the most freedom of all the managers - even more (in the past & overall) than the very successful Fergie.
It is easy to understand that players can let managers down and players might not play to their potential but in Wenger's case, he signed players that have very little scoring pedigree or fighting abilty or physicality, so it is up to him, and using kids is exactly is jis own making (it is not always about money with Wenger).
The manager has come out himself to say he has failed in some ways, why is it so hard for pijin to accept that Wenger is not beyond criticism; even your mate freddoc has criticised him. He takes the plaudit and he should also take the blame (note: I am not saying he is rubbish or should be sacked).