marcello said:

What autority can you bring in to support your claim that paper books use variable leading "almost exclusively"?

you don't need an "autority"; you only need to look at them. you will see, in any nicely-typeset book, that pagespreads are bottom-balanced and there are zero widows or orphans... and if you count the lines on each page, you'll find some spreads where they differ. this mix of facts means variable leading. period. now, i'm done with this conversation, thank you. you simply don't care to learn, so there's no point. if you are happy with your widows and orphans, i'm happy for you. some girls like their pimples. -bowerbird