I am suggesting that the label philosophical is usually attached to problems where we have no agreed upon methodology of investigation. Therefore whether a question belongs to philosophy or science isn't defined solely by its objective properties, but also by our knowledge, and as our knowledge grows the formerly philosophical question is more likely to move into "science" category. The point thus was that potential science isn't orthogonal to philosophy, on the contrary, I have expressed belief that those categories may be identical (when nonsensical parts of philosophy are excluded).

On the other hand, I assume philosophy and actual (in contrast to potential) science are disjoint. This is just how the words are used.