[jacques_chester]

I thought Cohn's book was good, but a bit padded out.

Basically all that agile really changed is how often folks take a sounding. Velocity is basically a productivity metric, it's a first derivative of project size (hence ... velocity).

But I mean you could always do that with traditional estimates.

That's pretty much what an Earned Value chart does.

Don't get me wrong: agile is an improvement. But it is an improvement that is evolved from what came before; not a categorical change. Looking at the historical literature still pays dividends to thoughtful engineers.