Propensity.. your logic is also right.. But khas/Gorkha bhasa cannot be called Nepali bhasa. From NEPAL you cannot call NEPALI bhasa can you.. but people of Nepal were forced to call khas/Gorkha bhasa as NEPALI bhasa.. which is wrong. Do you call Urdu language Pakistani language? You cannot defend NEPALI language to correct by using Grammar.. it's absurd. NEPAL BHASA is NEWA Bahasa. IT came from NEPA.. and always since beginning Newa bhasa was called NEPAL BHASA.. that's why we are accepted in UN.. not for Nepali bhasa. Je ma Bhaya.