I can't believe there weren't some terrible decisions against the Ausies in the 2006/7 ashes series too.
But that series didn't happen...
When you are dominating, you don't notice them as much...or they don't seem to matter as much.
I do remember Strauss getting a bad decision in that series though.
When you are a struggling side, you need everything to go right, or at the least not so much to go wrong.
Australia is basically on a hiding to nothing in this series. They are not expected to win any game...YET, when you have so many bad decisions go against you, it swings the momentum against you, thus putting you under more pressure.
It is hard enough for a good team to deal with, and basically impossible for a crappy team to make any head way at all.