My book is divided into two: the front half is a narrative introduction useful for folks learning software architecture, the back half is a reference section which should be helpful once they know it. I had written the previous chapter but then decided that it would make better reference material, so I moved it to the back. I attacked that chapter again, got halfway through, then got sick of it and moved onto this chapter. So my next task is to go finish up that previous one, so it should take maybe 10 days to 2 weeks. We will see.