I agree there is a lot of half hearted support in the stands, but to say that "lack of atmosphere is nothing to do with the configuration of the stadium" is simply wrong.
I sit in 232 and it's very often impossible to know who to join in with, as you have SS1, Kippax Corner and SS3 all singing completely different songs. Throw in the away fans and it just sounds like a mess of noise.
The point in the NS2 home end is that if everyone is singing in one voice, then it also makes it easier for the rest of the ground to join in.