I did a personal retrospective for a work project recently, on my colleague Cian's advice, and shared it internally at work. The experience—and resulting feedback—was positive enough that I wanted to write about it publicly. This culminated in us1 co-writing a Guide To Personal Retrospectives on our company blog.
Cian prepared a "roughwork" document with details of Who are we writing for? and What do we want to communicate? For me these have always been implicit, but I liked making them explicit: doubly so because we were collaborating. It's a trick I plan to steal, and do again in future writing.
A++; would do again.
Me being the "young priest" to Cian's "old priest" in this particular venture. Bring your own pea soup!