Not important. I had to look at my HCPCS to see what you were talking about. This appendix just gives the details of CMS publications that are referenced elsewhere in the HCPCS book. For example, under code A6550, they reference MED: 100-4,23,60.3 and that publication's details are written up in Appendix 4. I found it on page 126 of my copy of the HCPCS 2012 book.
The main thing for the HCPCS questions on the CPC exam is that you carefully read the question and pick out a code the reflects the details of the HCPCS item. Usually these are rather simple to figure out.