This is really it. "Birthers" can't respond rationally to questions and challenges because their motivation isn't rational. That's why they can't believably resolve the conundrum of
(a) there's a giant conspiracy covering up Mr. Obama's origin, which has already produced a fraudulent birth certificate, co-opted or tricked witnesses to supposedly valid documentation, produced phony newspaper ads in 1961, covered up parentage and/or foreign travel, and subverted or conspired with the State of Hawaii, both major political parties, various law enforcement agencies, and presumably the American Philatelic Association (why? because they could),
(b) but of course they'd believe a "long form" document released by this very same giant conspiracy.
It's the latter claim that is the cherry on top of the whipped crazy of "birtherism".