Forces all designs to be somewhat irregular by preventing you from building anything that would complete a straight line of 3 buildings of the same type with equal distances.

Each "type" of building (like all inserters, or all assemblers) blocks other buildings of the same type. You can disable specific types with the settings, or allow them as long as the line of 3 is at least a certain length end-to-end. Currently applies to most types of buildings.

If you try to place something where it's not allowed, you will get a message like "Too boring to place here (Long Inserter at 10 NE)" meaning that you were blocked by a trio formed with a long inserter 10 tiles north-east of where you tried to place something.

You can place ghosts that form trios, but when your bots try to build them, the ghost will disappear and your bot will carry the item back to storage.