You all know I'm always complaining about my memory, and I wish that more books 2 and later had a short summary of what happened before.
However, what I really, really don't like is all the "I remember when..." that characters do!
It breaks the plot flow. Most of the times it doesn't fit the character's personality. And it's really annoying, especially when it's done multiple times, and not just at the start of the book.
In particularly clunky cases, it jolts the reader out of the character's point of view, is that what you mean by "author intrusion" (or something similar)?