I love this article. Explains a WHOLE lot for much of the set up for Aragorn. This article led me to believe that there was more than one reason why Gandalf supported Merry and Pippin coming along on the journey. Their families had to have had ancient ties with the Northern kingdom and their presence in Aragorn's entourage would lend even further credibility to his claim to the throne. something even Denethor would not be able to argue against.
Just a theory...
It's an interesting "what if" to wonder how things would have proceeded had Denethor lived and survived.
I doubt he would have given up power as easily as Faramir did.