I got a few emails about this post and I guess it might have been a little too vague. The conclusion I was trying to draw is that we need more than one tool in out toolkits.
As engineers it feels intuitively right to have a single process, a single way to tackle every activity. Even though we say we don't we secretly quite like a good ole' fashioned IF/THEN. IF code like this THEN test like that.
Sure, we always need a framework to work in, a reference process to fall back on - just don't get dogmatic. Recognize that not everything you do needs to be treated exactly the same way (unless you have a really boring job) and stay flexible enough to be able to do the right thing in the right circumstances and take advantage of opportunity as it presents itself.
The best sort of engineering is about creating competitive advantage through technology - it's uncovering business value as you see it so whatever flavor your favorite bureaucracy comes in always make sure you're not structured to ignore opportunity.