[gentoo-user] Why is PS1 (the console prompt) different for the root user?

[Nikos Chantziaras]

I noticed that the root prompt does not include the full path of the 
current directory. Normal user:

   me@gentoopc ~ $ cd /usr/bin
   me@gentoopc /usr/bin $

However, for root:

   gentoopc ~ # cd /usr/bin
   gentoopc bin #

So for users, I can see where I am ("/usr/bin"). For root, I cannot. It 
just says "bin".

Now, I can change it easily in /etc/bash/bashrc (not sure if that's the 
correct place, but it works) by replacing "\W" with "\w". However, I'm 
curious as to why "\W" is used for root. When I have several root logins 
open (and I usually have to,) it makes it difficult to tell where I am. 
It says "bin", but am I in /usr/bin, /usr/local/bin, somewhere else?

Is there a rationale for this?