Donald Trump gave every indication that he would reveal more of his medical history during an interview on "The Dr. Oz Show" being taped Wednesday in New York City. Turns out, well, nope!

Earlier this week, in an appearance on Fox News Channel, Trump said he recently underwent a physical and was eager to release the results. "This last week, I took a physical, and I'll be releasing, when the numbers come in, hopefully they are going to be good," Trump said. "I think they are going to be good; I feel great, but when the numbers come in, I'll be releasing very specific numbers."

His aides gave every indication that Trump's appearance on "Dr. Oz," which was on the schedule before Hillary Clinton fell ill  Sunday and, in so doing, thrust the issue of health to the forefront of the 2016 campaign, was when he would offer a fuller picture of his medical health

In retrospect, it seems like Oz had never been promised the big reveal of Trump's medical records — or anything close to it. Look at this exchange between Fox's Brian Kilmeade and Oz on Tuesday:

KILMEADE: What if there's some embarrassing things on there?
OZ: Well, I bet you he won't release them.
KILMEADE: Oh, it's still going to be his decision?
OZ: It's his decision. You know, I — the metaphor for me is it's the doctor's office, the studio. So I'm not going to ask him questions he doesn't want to have answered.

Oz is not exactly Walter Cronkite there, right?

The abrupt change of plans will lead some to speculate that Trump's physical didn't go as he had hoped — and therefore, the release of its findings won't be coming anytime soon and especially not in such a high-profile forum as Oz's show. It's also possible that Trump wants to wait and see what Clinton releases — her campaign had promised to make more of her medical history public this week. That wouldn't be a bad strategy, but then why tell everyone that the release of the records will be on Oz's show?

Regardless of whether there is any there there as it relates to Trump's health, what this swerve affirms (again) is that Trump is something short of a perfect messenger for the transparency argument he and his aides are trying to make against Clinton. Trump regularly insists Clinton isn't telling the whole truth about her private email server and the way in which the Clinton Foundation operated. His surrogates have suggested that something is more seriously wrong with Clinton's health than she lets on. And yet, time after time, Trump moves the goal posts on his own transparency.

Although he hasn't responded to Hillary Clinton's recent health disclosure, Donald Trump and his campaign have repeatedly attacked her "strength" and "stamina" (Jenny Starrs, Bastien Inzaurralde/The Washington Post)

To date, the entirety of what we know about Trump's health — at 70 he would be the oldest person ever elected president — comes from a single-page letter written by his doctor Harold Bornstein. This is that letter:

Um, okay. The letter is, in itself, sort of remarkable — and not in a good way. And Bornstein has acknowledged (a) he wrote it in five minutes, (b) he was rushed to write it and he doesn't work well when rushed, and (c) the letter was heavily influenced by Trump's own descriptions of his health.

That's it. That's all we know about Trump's health with 54 days left before the election.

As I've written in this space, neither Clinton nor Trump is a fount of transparency when it comes to their medical records. But Trump's bait-and-switch — and that's clearly what this is — brings into sharp relief one of the defining traits of his candidacy: He promises one thing and then delivers another or, in some cases, nothing at all.

Whether it's how the wall along our southern border will be paid for, what he will do with the 12 million undocumented immigrants in this country or, in this case, his medical history, Trump plays a shell game. The ball, he tells us, is always under the other shell. Except maybe it's not.

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MANCHESTER, NH - NOVEMBER 7: Republican presidential candidate Donald Trump speaks during a campaign event at SNHU Arena in Manchester, NH on Monday November 07, 2016. (Jabin Botsford/The Washington Post)