Since you have quoted Jefferson in your tour de force of a post here is one by Churchill:
"It is always wise to look ahead, but difficult to look further than you can see."
It seems to me that, if we try to control the process of project planning too much, it becomes too unwieldy and inflexible. That is one reason for keeping only next actions in the context lists - the new version of the GTD Add-In helps a lot here by allowing future actions to be stored away from the lists. I agree with you that its project planning facilities are quite limited and I would only want to use it to plan the simpler ones. OneNote goes further - I've got it on order along with the rest of Office 2007.
But the thing that I need to have flowing more naturally is the easy use of multi-step projects for the more simple processes. It still feels unnatural but I guess with practice it starts to drop into place.
Thanks for your piece - a very interesting read.
(And good luck with the new business)