Three bullets before you open the thread

A forty-message thread is not information, it is archaeology. By the time you have read it you have spent ten minutes and mostly learned who was annoyed.

What you actually need before opening it is three things: what was decided, what is still open, and what is waiting on you.

Ask for those three, not for a summary

The word "summarise" produces a proportional retelling, which for a long thread is still long. Naming the three sections is what makes it short.

Summarise this thread as exactly three bullets:

  DECIDED   what has actually been agreed, and by whom
  OPEN      what is still unresolved
  ON ME     what is waiting on me specifically

If a section has nothing in it, write "nothing". Do not merge sections to
avoid an empty one.

Do not describe the discussion. If someone raised something and it went
nowhere, it is not decided and it is not open, it is noise.

Quote the sentence that settled anything you list as decided.

Requiring a quote for anything "decided" is what stops the summary inventing consensus. Long threads are full of things that sound agreed because nobody objected, and a summary that promotes those to decisions is worse than no summary, because now there is a document people will point at.

Use it before you open, not after

The temptation is to read the thread and then check the summary. That gets you the reassurance and none of the time back.

Read the three bullets first. If ON ME says nothing, you are done. That is the whole return on this.

Make it standing for the threads that need it

When a thread reaches ten messages, write the three-bullet summary into
the thread as a draft, so it is there when anyone next opens it.

That version helps everyone rather than just you, and it is often the thing that stops the thread growing to forty in the first place.

What good looks like

You open a long thread already knowing whether it needs you, and most of the time it does not.

The failure to watch for is DECIDED filling up with things that were merely suggested. If that happens, the quote requirement is being skipped, and it is worth insisting on rather than softening.