Warning: this post is not a direct answer to your question.

Why don't you put those unprocessed tasks in your inbox and treat your inbox as a processing area?

You should be able to search for NOT tag:processed to get the results you want.

Also, you may be able to skip the manual tagging and search for tasks you need to process, depending on exactly what you need to add. Something like priority:none OR due:never OR hasNotes:false, etc. Of course, my example would only work if you want your tasks to have all three properties set. I have a list like this that looks for my required tags or anything in the Inbox and I've incorporated that into the Smart List I use daily so that I can easily spot anything I need to process.

txtxyda: The thing is I don't mind things living in the inbox. if they don't make sense being added to lists - feeling like I am forced to add certain tasks to lists, to get them out of the inbox would only create clutter in my setup. Good suggestion though.

andrewski: You sir are my favourite person of the day. I like your setup but having one as simple as this should work for me so long as I can remember to at the tag "processed" every time a task has all the info needed.

Thanks guys, much appreciated!

I think what Andrew was suggesting was through the creation of a check list, one can determine if all of one's tasks are properly annotated without needing to add the step of adding another task, such as processed. Many of us here on RTM have a series of check lists we use to ensure things don't fall through the cracks.