Opening Manor mount to two way traffic would make it a thoroughfare to the south circular obstructing the road and making it impossible for ambulances to get out of their station. Also making it dangerous to enter the south circular at the now renovated junction

Honor oak Road whether you like it or not is the widest most appropriate thoroughfare it can support heavy traffic and is two way (unlike all the other roads around which are hilly,weight restricted and basically one car wide)
It is wider than Dartmouth road which is an 'A' road