Except ignoring WOJ isn't a "perfectly acceptable analytical framework" as you put it. We're not dealing with science here. This is fiction. Jim sets the rules. He can change them as many times as he likes. We don't have to like it, but that's the way it is. He would probably lose his readership if he did it too often and overtly, but that's his choice. It is not the right of the reader to choose what elements are true and what are not. We can have opinions, but it's Jim's ideas. We didn't create it. We might ascertain meaning that Jim didn't intend, we might see things that are only created by reading from our perspective (which are not invalid), but we cannot change the facts of the books just because it doesn't suit us. That is arrogant in the supreme.
I suppose this is where we fall out and decide not to be friends.
On this board and in this context, when arguing we have to agree on shared reality. Please don't confuse this with facts. Fact are unchanging and they never have to be retconned. The books are not a unified whole. And they aren't a unified whole in the mind of the author. If we limited ourselves to the text, there wouldn't be anything to discuss. We analyze emotions, intentions and things never revealed in the text. You may read that as I/we make shit up.
In the case of souls and spirits it makes absolutely no difference in how you parse them. They are interchangeable in effect, if not in fact. They are different only because Jim says they are, even though, when he writes, there are no markers that would let you analyze what each is. So for instance, if Harry is a soul wandering in the world without a body, is there any difference between him and Sir Stuart as a pure spirit? You might also ask if Harry's spirit is wandering and not his soul, where is his soul, and what's it doing while his spirit is out on the town? And in terms of spirits he has created at least four who can manifest, the Archive, Bob, Bonea, and evil Bob. Not to mention Lash who is a !!!Shadow!!!.