Observatio · 02 Reader retention

The margin is where the reader stays.

Completion rises as the page gives the eye room to return.

Completion rate by page treatment
Four layouts · 1,240 sampled sessions · chapter one
highlighted reading treatment
100% 75% 50% 25% 0% 48% 61% 74% 83% Quiet margin Balanced Generous Wide + notes page treatment THE DIFFERENCE +35 pts from a quiet edge to a wide, noted page. THE FOLIO HOLDS when the eye can rest.
This is the Gutenberg 42-Line Bible design system, applied by Curio — a design-style library for AI agents. Full Gutenberg 42-Line Bible guide → designbycurio.com/learn/gutenberg-42-line-1455