I can think of one non-fiction book in particular that benefits hugely from being read as a summary[0]. The E-Myth contains some great information, but the storytelling style it is written in is absolutely excruciating.

[0] https://sivers.org/book/EMythRevisited (I liked this summary - I found the link a few weeks ago on here. Thanks to https://news.ycombinator.com/user?id=sivers)