(FORTUNE Magazine) – Thanks to an exchange between Chairman Sanford Weill and a questioner at Citigroup's annual meeting in mid-April at Carnegie Hall, the company's shareholders gained a new, deeper understanding of just what "full disclosure" means. The interrogator was Dr. Clint Weiman, who identified himself as the former medical director of Citigroup's predecessor, Citicorp. He wanted to know about Citi's succession plans and Weill's health.

Weill, 68, expounded on his health energetically, reeling off some wellness statistics that he'd obviously been busting to discuss. He said his blood pressure was 128/80, his cholesterol 183, his "good" cholesterol 68, and his lungs free of problems (a point he made, perhaps, because he used to be a heavy smoker of cigars). Dr. Weiman seemed bemused by the extravagance of the answer and looked ready to move on. But Weill wasn't finished: Forming a thumb-and-finger circle and grinning, he said, "And my prostate number"--we assume he meant his PSA reading--"is close to zero."

Was that possibly a first for a Carnegie Hall soloist?

Next, under Weiman's prodding, Weill, who has no interest in retiring, moved to the subject he detests, succession plans. He said he was engaged in a "dialogue" with the board about that topic. Weiman persisted, recalling that a former chairman of Citicorp--yes, Weiman said later, it was John Reed--had said he saw no one below him who had the "energy" to handle the CEO job. Weill demurred. There were definitely good candidates inside, he claimed, but he didn't think it was in the interests of anybody to name them publicly.

And, besides, maybe none is as healthy as Weill?