As soon as I hit 'publish post' on that last post, and ever since, I've been second guessing myself. Can I really put all of polymer clay into three categories?
I can, partly because these are my own made-up categories, but also because I have a (slight) explanation.
What to me is the absolute coolest thing about polymer clay is all the colors! Between the different manufacturers having slightly different takes on their pallets, and the fact that you can mix any color together with any other color to make a new color, like with paint, the color choices are unlimited!
And using the color of the clay to be the color of what you are making is the basis of both sculpture and millefeori, everything else you are more using the clay as clay, and the color plays a great role. Maybe the third category should be 'everything else'.
I have often called polymer clay 'color clay' (especially back when no one knew what poly clay was), and this separation is kinda the difference between if you are emphasizing COLOR clay or color CLAY. Symbiotic both ways.