Agile in the real world

Mike in IS449 raises an interesting point:

Agile Web is a great concept, but my dad's business doesn't implement that process of producing systems if I understand him right. He is still mainly directed by the systems design life cycle, most of the time less than even that because of the demand of customers. So are the theories of agile the direction the market is moving or will it be an even more refined era of systems integration that it heads to? It is hard to tell but it will definately be notably important to be familiar with both.Mike Souders

To which Jeff Atwood at Coding Horror seems to respond:

Often, you can't even begin to accurately estimate how long something will take until you start doing it. At least some of it. That's why so many teams turn to agile, iterative development techniques; part of each iteration involves exploring all those unknowns and turning them into slightly-less-unknowns for the next iteration. The faster we iterate, the closer we get to an accurate estimate, and the more work we get done along the way. We plan by doing.Coding Horror

You should also have a look at this interview with Rich Sheridan of Menlo Innovations: Innovating in a Mature Market.

The real point though is not that agile is great, rather it's that project management is about mitigating risk. SDLC takes one approach to risk mitigation that relies on extensive pre-implementation planning. Agile takes another that relies on attempting to implement components very early on and then re-estimating effort for the whole project based on actual data. People have turned to agile methods because they feel there is often not enough accurate data to undertake the detailed planning required to make SDLC succeed.

However, at the end of the day, as Mike notes, you're really obligated to communicate with the people who are paying the bills and use the method they require.