So what do you suggest? That the Supreme Court reconsiders every damn case, even though they dismissed a similar case a week ago (hypothetical). You do know that we need many more justices and an circuit court system to handle that load, don't you? And how would lower courts handle cases, if the Supreme Court treats its own precedents like toilet paper? I don't think that it would be workable.
And precedents don't just get followed for the sake of following precedent. That's why Plessy eventually got overturned by the activist Warren-court.
I don't believe in a living constitution, but I do know that the founders intended the constitution to last for centuries. So I am not so big a fan of Scalia's originalism, aside from the fact that it threatens the stability of our system. (I hope I don't sound like a flaming liberal.)
I really don't think there's a middle ground here. Either you believe the constitution is living or you are an originalist.
I am not suggesting the Court reconsider every case. I am not even suggesting they reconsider any one case. However, if the Court gets a case in its docket, rather than simply looking for old cases, and seeing how other Courts ruled, why not (warning: Revolutionary Idea) examine that case on its own Constitutional merit, and rule accordingly? Following precedent is ok, if the precedent is sound to begin with. Otherwise, it simply compounds prior errors.
The Framers, our Founding Fathers, meant the Constitution to stand the test of time, or as you say so well, last for centuries. However, when it gets constantly re-written, based on the agenda of nine un-elected people, who have lifetime appointments, and who consider themselves the Last Word, then our Constitution starts to lose that ability to outlive each and every one of us. I would rather have Justices who read the Constitution looking for the Founding Fathers' original intent, instead of the modern meaning.