Even before the release, there were multiple reports that indicated the White House knew the memo had been oversold. The Washington Post's Philip Rucker, Ashley Parker and Josh Dawsey reported that White House Chief of Staff John F. Kelly on Wednesday “shared with the president his opinion: that releasing the memo would not risk national security but that the document was not as compelling as some of its advocates had promised Trump.”
Axios's Jonathan Swan reported that “inside the Trump administration, sources who've been briefed on the Nunes memo expect it will be underwhelming and not the 'slam dunk' document it's been hyped up to be.” The New York Times's Maggie Haberman tweeted that the prospect of a flop was “more than fear for a number of folks who have been told of its contents.”
If the memo were as explosive as advertised, Republicans could have made it public earlier in the week or held it until the beginning of next week to maximize exposure. The Friday-afternoon news dump is an age-old strategy to minimize attention. Fridays before holidays or major news events provide especially good cover.
You might recall, for example, that Trump dumped his order to ban transgender people from joining the military and his pardon of former Arizona sheriff Joe Arpaio on the Friday that Hurricane Harvey made landfall in Texas.
Or maybe you don't recall — because you were focused on the hurricane. That's the whole point.
The memo's release at a time typically used to bury news suggests that Trump and fellow Republicans might not buy their own hype. They eagerly fueled speculation and anticipation but perhaps concluded that the idea of the memo was better (for them) than the memo itself.