Secrets of Slam Dunking

Former CIA Director George Tenet is wrapping up a memoir, scheduled to be published this spring, that will, among other things, explain the "real context" of his remark to President Bush that the case against Saddam Hussein regarding Iraq's weapons of mass destruction was "a slam dunk." Based on the account of "one person who has read early drafts of the book," The New York Times tries to explain Tenet's explanation:

Mr. Tenet defended himself by carefully parsing the "slam dunk" comment: he said he was not telling Mr. Bush that there was rock-solid evidence that Mr. Hussein had chemical and biological weapons, only that the president could make a "slam dunk" case to the American public about these weapons programs.

Does that mean that, although the evidence that Iraq had WMDs was not rock solid, Bush easily could pretend that it was? Or does it mean that, assuming the evidence was rock solid (which it wasn't), no one could reasonably question the need to invade? The latter, it seems to me, is clearly not true (although I may be a little biased by the fact that I opposed the war even though I thought it was likely Saddam had substantial WMD capability). The former seems more plausible—indeed, pretty close to what actually happened. But why does Tenet think he looks better by arguing that, rather than naively passing on bad intelligence or consciously exaggerating its strength, he was advising the president on how to fool the public?