Hi Wouter! I think you’re right, if I’m understanding correctly: Those stages don’t need to be progressed through on a linear basis, and in fact thinking your work will go that way can block you. Rather, these stages are components that make up creativity. Even when Graham Wallas named these categories in The Art of Thought, I believe he accounted for that.
This is why I prefer to think about my actual work in terms of the seven mental states. Many of these mental states can be used in various stages of the creative process. In practice, I find these mental states to be incredibly useful.
The other important thing, I think, is to merely be aware of the importance of incubation. When we’re used to doing work that is procedural, working with the natural flow of creativity is counterintuitive.