My partner and I made up this acronym because we like to revisit subjects often, a valuable practice.
When subjects are revisited, misunderstandings can be exposed and corrected, changes in opinion can be voiced, new evidence or insights introduced.
Saying “ISTB” cuts off the horrible default response: “You already told me that…” or the feeling that such a response could be appropriate.
ISTB signals that either new information is forthcoming or the speaker wants to ensure that something—possibly something very subtle—has been understood in the way intended.
It might also simply signal that the speaker feels like saying what will follow for no other reason than that.
We say ISTB by just voicing those four letters out loud.