I'm not aware of any large scale projects that were attempted using Agile. Are you? FWIW, I don't think Agile is the answer - there's a continuum between (and beyond) waterfall and agile, and it's not one-method-fits-all anyway.

For that matter, I can hardly think of large scale software projects that succeeded in the sense that they were on time, on budget, and satisfied the requirements a-posteriori, regardless of methodology.

Regardless, how many projects that people here are involved in are really large scale ?

I'm not defending agile, but what is described in the abstract cannot fit with what I am familiar with as "agile" - an almost defining quality of an agile process (as I was introduced to it) is that at any given moment, the status of the project is transparent and well known by all stakeholders. Thus, if you discover all of a sudden that the project is late and over budget, you have been sleeping at the wheel.

(Note: This is not a "no true scottsman" argument. And I honestly think agile is only a good match for some projects, and not e.g. infrastructure. Nevertheless, this does not sound like the "agile" I know).