Can TUNIX be used as a guide for writing an operating system ?

Dear friends, Ive gathered the following information regarding TUNIX and I have found a link to this book with respect to TUNIX : http://www.alibris.com/booksearch.detail?invid=9970583309&qwork=4865440&qsort=&page=1

Tunix:

Tunix is a small linux distribution/toolkit, intended to teach and show how to gather opensource projects, what parts are needed, what methods can be employed and as a result, have a bootable linux distribution which fits in a single disk or CF card.

Tunix is a set of tools used to generate small bootable Linux images. It can be used to learn how to roll your own distribution, or to port embedded systems. The basic release uses busybox and has a kernel with netfilter-enabled modules. A uclibc iptables binary is included, so you can roll your small firewall from a floppy.

Kindly enlighten me regarding the above query !!

Thanks !