Audience member heckles Boris Johnson during hustings

The transcript covers a discussion on the importance of keeping civil servants' advice to ministers confidential and the consequences of leaks. It also touches on the appropriateness of discussing a diplomat's career in a TV debate and reflects on how questions could have been answered differently in hindsight.

What does the speaker imply about the handling of confidential information?

In retrospect, what does the speaker wish regarding the subject discussed?