One of the two sources said Horowitz's investigators appear to have found Steele's information sufficiently credible to have to extend the investigation.

The key here is that if a central bank is sufficiently credible then it should be unnecessary to intervene in the first place.

The latter is just sufficiently credible to make me think at times that I have missed the most brilliant opportunity of my life.

But it comes from a document deemed sufficiently credible by US intelligence agencies that they briefed both President Obama and Trump on its contents.