neither in the original papers nor in current implementation you will find any hint that PR is treaten differently for internal than for external links. You can easily make such investigations which will show this.
However, it seems that Google distinguishes between internal and external anchor text (but not PR).
By the way I'm making no assumptions. Apart from reading the papers and making numerical and analytical calculations, I have made detailed investigations of Google implementation/modification of the PR algorithm. Therefore, the statements are not only based on calculations but also on studying/verifying these things. Have you done this?
To say it again: I never said outgoing links are bad. I'm considering outgoing links (e.g. to Google) no kind of reciprocal links. By the way, even reciprocal links can decrease PR - it simply depends on the PR of the pages.
People who post [webmasterworld.com] statements like this
shouldn't talk about 'nonsense'. Even with simplest math one can disprove this statement in one minute and one will find that the total PR (sum of all pages) of all Widget, respectively, Blodgett pages will be the same (of course, the distribution is different). The advantage of cross linking is due to anchor text and not PR. (And those who don't believe in that calculations can even verify this in practice.)