I don't. But, I do expect you to point to either the administrative function that you claim - by asking for Mandamus - hasn't been executed by the Legislative Branch? What is it?
"So, since you keep bringing up the USC, I'd ask in reply, why do mandamus issues have to be addressed there, instead of the Constitution itself?"
They don't. If, for example, the Electoral College refused to meet or refused to vote, I imagine a person with standing could sue, citing Mandamus, to have the judiciary compel them to meet or to vote - unusual, but I suppose it's theoretically possible. But again, what Constitutional task hasn't been executed that you would request Mandamus compel be executed?
"As for the actual requirement, perhaps you missed the part of Section 3 of the 20th Amendment that states ""
Wow. That's an increasingly popular one. Someone beat you to it, just a few posts up. Once again, you understand that 20 sec 3 deals with contested elections, dead Prez or VP Prez, or both or some other Electoral College crisis, right? Qualify, in the context of the Amendment, is referring to someone actually not qualifying. But, Obama & Biden were qualified. How do I know that? Because both were certified, multiple times in complete accordance with Constitutional and Statutory law.
"then to argue that there is no Constitutional remedy"
Who's arguing there's "no Constitutional remedy"? If Obama perjured himself when signing 50 certificates of eligibility (which is what my state of OH calls it, another state may call it something slightly different) that he submitted to each state, under penalty of perjury, that he's indeed a Natural-Born citizen, then that's a matter for the Legislature. I went to law school quite a while ago, but I'm fairly confident perjury is still a "high crime & misdemeanor", right? Looks like it's a clear case for Impeachment, and thankfully Impeachment just happens to be the prescribed Constitutionally remedy.
Every element of the election of Barack Obama that was subject to judicial review - to include all the prerogative writs - was either met or successfully and fully executed. And, equally importantly, all the people that are legally tasked/empowered to challenge these qualification or standards or administrative tasks, didn't. Not one Secretary of State, not one Elector, not one legitimate candidate and none of the Constitutional officers of Congress objected when it was their opportunity to object.
There was a judicial remedy to this problem - to the extent that there is a problem - before Obama was inaugurated. There remains a remedy for this problem today, but it's only a remedy available to the Legislative Branch - exactly as the Constitution demands.
All of your "objections" refer to this basic circular argument - you say that because Obama was certified as qualified, then he is qualified. In other words, your position is that any challenge to his qualification must take place upon the presumption that the qualification was valid, because - it took place.
But my disagreement is based on the long accepted legal effects of fraud, which is that it vitiates all process. Which means that if the certification of qualification was fraudulent, then the certification was fraudulent, and if the certification was fraudulent then the qualification never legally took place at all.
And while perhaps presumption of legality could force an initial presumption of qualification, and thereby require a tortuous legal process to get "standing" for a challenge requiring legal review (i.e. the whole birth certificate mess), such presumption of legitimacy would not be justified in the case of prima facie evidence of fraud.
And what is the admitted non-American citizenship of Obama's father but prima facie evidence of the impossibility of his having natural-born citizenship?
So given that, I can't see how the certification of his qualification under 3rd/20th could be seen as ever being legitimate, since it is openly, obviously impossible. Thus, the certification of his qualification was falsely affirmed, thus qualification never legally happened.
Given all of this, if you still believe presumption should be given to legitimate qualification, there isn't much else I can say, except that I don't see your escape from the vitiating effects of prima facie fraud - and that it would be nice to see this issue addressed by SCOTUS.