I have to admit I only made it about half way through this, by which time it seemed to me that the authors had little more grasp of the concept of irony than Alanis Morissette.

Irony is neither cynicism nor snark. It is an indispensable aspect of most forms of written expression; it is almost impossible to write a successful work of opinion or fiction of any length without mastering this classical tool of rhetoric.

Where would Shakespeare be without irony? And what of the ancient Greeks? It's not modern, it is a connection with our heritage.