From Moses Gates's "Hidden Cities," p. 79:

We come to a building covered in scaffolding, which Steve starts climbing up without even pausing to look around for cops. I don't really want to follow, mostly because I'm pretty drunk, but I feel obligated. So I start up the scaffolding.

And it's wonderful. Everything is easy. There's no freezing, no nervousness affecting me physically. It turns out there really is something to the expression "Dutch courage." I can't imagine why I haven't done this before.

Climbing while inebriated is something I really shouldn't recommend, but I will anyway. Now, I'm not talking about drunkenly trying to scale a rock wall at Yosemite or anything, but in those instances when the mental barriers are significantly greater than the physical barriers, the combination of booze and adrenaline can be magic. The mental barriers are washed away, while the physical barriers are still a long way away from being truly tested.

End quote.

I also think having a drink or two beforehand can only improve your confidence and naturalness, which can in turn make conversations with suspicious security guards a little less awkward.

Being totally sozzled, with a can of beer in your hand, might be another matter. Then again, everybody can understand the drunk. Not everyone understands the ninja taking photos of their abandonment at 2 a.m.