Just a thought...
I'm very well educated in traditional, structured Project Management techniques. All that being said, I'm not sure that GTD isn't on to something:
- come up with a vision - it might be completely unrealistic
- if you do enough things, eventually you'll get to a good enough place.
It's a kind of naturalistic approach to Project Management. I'm not sure it isn't worth more thought. Many a project has exceuted perfectly using structured PM techniques and been a complete failure (and vice versa).