I don't think Shane "gets" totally shitfaced....I think he just pretty much "is" totally shitfaced.
That said I thought the show was pretty good. I was there the first night. I didn't think sound was that bad...there was some occasional feedback (monitors I think) and there was one song where things went pretty wrong soundwise but other than that OK. Not the best but not terrible sound.
Shanes voice held up better than I thought, some of the material he sounded quite good, but he's got a great band to carry him.