I ask you. Look around here and tell me if you really see any loons in the house? Take a good look. That's right...there aren't any. You've got to spend some time at DU to experience some real insanity.
That being said, the answer to your question is Yes, nearly all of the controversy would disappear overnight. Of course, there will always be a fringe element that can't let go of even the most crackpot conspiracy theory. If Obama were to end this by producing his original birth certificate, you'd then be able to spot the real loons, because they'd be the only ones left talking about it.
So from Obama's point of view, he gains no advantage by producing the original birth certificate even if he has it. Rather, he just draws attention to the controversy and gives it credibility.
This really isn't a "controversy" as we normally think of them. Lots of controversies are manufactured, or cooked up attacks against political opponents to injure them in the press. This is a whole different kettle of fish.
So, where is the press? No press, no controversy, right? If it's not on the boob tube day and night, then it's something else. Just the fact that the MSM is silent on this, or gives it snickering short shrift, indicates to many Americans that something almost sinister is happening.
This is about as simple an issue as one could ever see in a presidential election. The DNC and the Secretaries of State across the nation did not check Obama's credentials before they allowed him on the national ticket. Apparently, there's no mechanism in place to do that, so it's a sudden and glaring error discovered in the process. Well, the Constitution says that a President must be a Natural Born Citizen. Ok. Mr. Obama, sir, we're very sorry about this, but we'll have to ask to see your ID, if you don't mind.
Obama gets his people to procure a copy of his original BC, and it's over in 72 hours.
That's what an honest man would do in these circumstances.
You say there's no upside for Obama in this? How about being able to begin his presidency without the suspicion of illegitimacy hanging over his head? How about knowing that he won't be continuously challenged in the courts about this for the next four years? How about knowing that this controversy won't be constantly sucking the life away from everything he attempts to accomplish? How about knowing that he'll be recognized as the legitimate President of the United States by every world government, without question, and that treaties and agreements he signs will be looked upon as valid because of that? And, how about knowing that he won't provoke half the citizens in the country to openly rebel against what they see as illegal usurpation of their government?
There's a lot of upside for Obama in ending this controversy.
I respect your opinion, although I happen to disagree with it. I think a plausible argument can be made either way.
The fact remains that Obama has chosen a different path. One possible explanation is that he was born in Kenya and hence must go down this path in order to become President. Another possible explanation is that he has weighed the advantages and disadvantages, and has concluded that he's better off politically by treating the entire matter as frivolous and ignoring it.
In the latter case his political judgement (or that of his advisors) may turn out to be wrong, but it nevertheless explains his actions. And from a practical viewpoint his present course of action will not prevent him from becoming President, and it will not matter to the vast majority of the public.
It will matter to his most vociferous right-wing critics, but I don't think Obama is concerned about appeasing them.