I've built something that takes chunks of a book, in order, like 2-3 pages, and rewrites them in a more condensed format, like 40-60% of the original. Is this something useful to you?

That sounds super useful!

Let's give it a go, send me your book and i'll send you back the output. Or title and maybe i can find it online somewhere.

Here's an example of 53% reduction of Walden, for your kindle: https://file.io/ynZg5xEzxAhD