I often work on long books - 400 pages plus and the facing pages have to balance on the bottom baseline. Number of lines per page has to stay the same. I am always going through using tracking to try and pull a line back or add a line which is a pain when a book is full of short paragraphs. Anyway that this can be automated with a script to either use tracking or character spacing to balance out pages without affecting the number of lines per page? I know this could be done on an old typesetting system I was using back in the early 2000s before switching to InDesign, surprised that there is still no automation for this in InDesign yet.