I agree with Nick, it would help in historical situations as well. Sometimes projects have cross use-cases and only being able to choose one Program/Portfolio really limits the way we can organize them for future reference.

Sometimes there are Projects that "belong" in more than one Portfolio, for instance we have a Publication Portfolio and all ad projects belong there, but an ad project may also be associated with a specific Product Launch Campaign. We have to choose which to keep whole, instead of being able to keep...