I love models. And I particularly like semiotics (Peircian) and activity theory. These models are extremely useful as analytical frameworks and I have even seen designers (e.g. Tom Ockerse)  attempt to use them as generative tools. I found the Thwaites/Davis reading added some useful concepts/terms to my understanding of semiotics. My concerns with the semiotic model is that it is hard to place the author/creator in there. Here is a quick addition to the diagram I posted some time ago. I’m not sure that it fully addresses the relationships — but here it is anyhow.