Cebu's streets are way too NARROW to accommodate a BRT. Most of the major roads in the city are only 2 lanes. A BRT will take 1 lane. What will happen if a jeepney drops off a passenger or an old car breaks down on the only remaining lane?
BRT is only used in major streets not on all two lane streets. Besides you can have a BRT without a dedicated lane. Study the bus system from other countries in the world hindi ba maka kita ka ng mga buses on a two lane road. The one that is funded by the World Bank is called a BRT but technically it is just part of a mass transit system and you can call it anyway you want.