That seems like it would be (almost) the same as a clean install.
However, it is still much harder than having /home on a separate
partition and then just letting the installer format the entire /
filesystem (along with whatever other partitions you are using for the
OS).
Doing it that way means you have to do an rm -rf /<directory> for each
directory that you want to nuke, and having to also remove any files
in / itself... All the while making sure you do not remove /home.
Is there more than one way to skin that cat? Sure.
Some are simple and others are needlessly complex.
Also, to do things this (tedious) way, you need some other OS to boot from in
order to mount / whilst you wipe from it the things you want to...
Its so much easier to just stick /home on a seperate partition, I really don't
understand those who recommend this way, but each to their own I guess...
Chris