I seem to recall David Allen saying that the line between Someday/Maybe and reference can feel blurry. A significant fraction of my S/M’s are things I might want/need to have as an option under the right future conditions. Items which are “Next time in Seattle” may be relatively easy to recognize, collect and organize, but not everything is. I think I do ok by asking the “where and when do I want to see this?” question.
One trick I use sometimes is to use a question mark in an item to trigger consideration: “Clean attic?” I think this works best with a digital list manager that accommodates start dates and recurring items, but you can do it with a paper tickler system. Sometimes I put the trigger in explicitly “Clean porch roof when enough leaves accumulate?” The question mark is not really grammatical because I’ve written the action in the imperative, but it’s just a trigger.
