I'm not sure you're doing what most gtd'ers would do. The typical project cycle is something like this:
1) Project surfaces and is placed on project list with desired outcome.
2) At least one next action, doable now, is identified and placed on a context list, i.e., @computer.
3) Any other plans, notes, et cetera goes into project reference.
4) Next action is selected from context list at appropriate time and place.
5) Work on project is performed. Project reference consulted as needed.
6) If the project is not done, do 2), else done.
7) Do something else.