I think we're perhaps debating the wrong thing here. Pretty well by definition any 'Chinese' dish a Chinese chef knocks up in a Chinese kitchen is 'authentic' - even though it may be the local version of the dish rather than the original version.

A better question would be what is 'typical' Chinese food. The answer probably being that it's what your 'average' family eats on a 'average' day in an 'average' home or an 'average' restaurant.

How close to typical a visitor gets really depends on where they go and how close to typical they want to get.

The stuff that gets presented to Western tour groups is choosen on the basis of what they will probably like and be familiar with rather than for how typical it is - in the same way Chinese restaurants in the West have menus featuring the stuff that tends to appeal to Westerners. Upscale is also never very typical.

As I said in an earlier post - go to any 'mid level' restaurant with Chinese. You'll be eating typical/authentic food.