Thanks... but all the things you're describing are still all linear though in terms of servers, no? All the services you're describing will scale linearly.

And if some external bottleneck exists... that's a separate issue and adding more servers isn't going to solve any problems at all.

I guess I still just don't see it... I know servers don't scale "exactly" in the sense that one service will require another server before another service does, but that doesn't make it nonlinear. It just gives it variance (fluctuating both upwards and downwards) around a line. It doesn't turn it into a curve.