The longer I think on this, the more convinced I am that GTD really doesn’t ask you to do much with your lists. Simply moving things from your inbox and categorizing items by appropriate context (most people only have 5 or 6 at most, in my experience) takes a few minutes, possibly mere seconds with most software based solutions, if you do it once a day or once every two days.
I will grant the weekly review takes some more time, when you are going through your projects and identifying the next action and so on, but this is absolutely essential thinking that must be done anyways if you’re going to make progress on your projects. You’re just doing this “up-front,” batching together your thinking so you’re more agile and less-stressed later.
All of these seems very appropriate to me. I think the real issue is that if you’re spending hours managing lists, you’re either:
1) allowing yourself to be distracted with the tool 2) you have an overly-complex tool 3) (and I think this one is most likely) you’re over-committed.
A principle way GTD reflects back to you that you have too many commitments is when it’s taking a disproportionate amount of time to review and process your inbox and next-actions lists.
You’re overly committed if you can’t find 15-20 min per day to clear your inbox. Similarly, if your weekly review is taking 3+ hours on the regular because you are overwhelmed with projects, it’s also likely you simply have too much on your plate.
I know I’ve over-scheduled my week when I can’t fit in my 1.5 hour weekly review, or when my inbox goes a 3 days or more without being cleared because I’m just too busy.