I don't think it is a good idea since the line is already overlaped with 70K
273 and 273A are more frequent compare with 70K
and I think that it is better for the 270B not via Jockey Club Road since the 70K has already via.
I would suggest that the 270B will via Ma Sik Road to LWH and have a exchange with 70K in Fanling Town Centre, a interchange of 273/273A in Fanling MTR[more prefer]/Cheung Wah Estate.
The thing about you interchange suggestion of 70K: I think it is better to make it Fanling Centre-->Wah Ming and Jockey Club Road-->Fanling
But I still suggest not to via the Tai Wo West Service Road except the special buses at peak hour.
We may convince the Tai Po District Council by a cheaper interchange price.
We can provide a 2.9-3.7 interchange offer for 73 and 271 which the total fee will be lowered by 0.7-1.5