Put beans in a pressure cooker; add water, oil, salt, and marjoram (if using). Bring to a boil, covered with a lid from another pot, not the pressure cooker lid (you don't want to build up pressure yet). Remove from heat and let beans soak at least 1 hour, or up to 3 hours.
Put on pressure-cooker lid, seal, and bring up to full pressure over high heat. Reduce heat to low, maintaining full pressure, and cook for 12 minutes. Allow pressure to reduce naturally (do not use quick-release method), which takes about 15 minutes.
Transfer beans with a slotted spoon to individual serving bowls, and serve with a drizzle of olive oil (if desired) and desired accompaniments.