From what I've been reading, the nofollow coding should be included if you don't wish to pass page rank to a link. While this makes sense to me for a link to an external site, should this coding be included on pages within your own site?

My question is then: is there a certain amount of page rank that your site has as a whole? If you continue to add additional web pages, are you in fact diluting the overall authority/page rank of all the pages?

If yes, should you use the no follow coding to keep new pages (that don't necessarily need to be ranked) to keep the PR/authority on the more important pages?

For example, should you add this coding on a product page on your site that has links to various relevant product information pages? In my mind, while there are lots of pages that are great for informational purposes, they don't necessarily need to have page rank passed on to them -- I would prefer to keep that on my most important pages.


Any validity to my thoughts?