The Jacoby rule: no gammons until someone doubles

A gammon or backgammon counts as a single point unless a double was offered at some point during the game. Standard scoring pays double for a gammon and triple for a backgammon whatever the cube shows, which rewards sitting on a won position and grinding out the extra point instead of doubling. Use it in a session scored game by game, not in a match played to a fixed number of points.