Sir John Chilcot and co will have been especially gratified by the public gallery's spontaneous applause at the close of today's session.
Perhaps it was euphoria at having made it through nearly four hours of evidence from the former secretary Jack Straw, but the audience seemed distinctly pleased after Sir John passionately - by civil service standards, at least - reaffirmed his determination to do a good job.
His statement rebutted many an accusation levelled at his panel by the media in recent weeks: the inquiry was "committed to being open and transparent"; "we have no reason to believe any material is being deliberately withheld" by the government; and "the inquiry has broken new ground".
I've been a member of the audience two or three times so far and have noticed one or two familiar faces each time. These committed individuals tell me they're impressed by the panel's work and are more dismissive of journalists than the non-forensic nature of the questioning.
As one pointed out, the purpose is to get new facts to come to light; there has been some success here.
Perhaps more importantly, the questioning has been getting more and more forensic recently. Today's session - especially the scintillating 40 minutes - was riveting as Straw wriggled on the hook of legal advice for the war.
"Nicely done," Lawrence Freedman whispered to Sir John as the applause died away, the grins showing on all five of the panel's normally serious-looking faces.