If it would be economically viable to have the same thing manufactured in Xinjiang or Qinghai, and shipped by road, it would be a huge boost for those areas. Especially if linked through Pakistan's road network to sea ports, bringing easy access to Middle East, Europe, Africa as ships would no longer have to navigate via Singapore.
An in reverse, it would be a huge diversification of import routes for commodities could come in via another route. Not oil specifically, but all kinds of bulk. Bulk carries of commodities are far less efficient than oil ships, the largest with a capacity of 100,000 tons but 30-60k capacity more common (far less than the capacity of a supertanker). So commodities needed to develop the west of China now have a simpler, more efficient route.
Here's a partial list of projects being funded in Pakistan by China.[2] China's government seems determined to get a land linkup to Europe. Yet this isn't the main "New Silk Road" route - that's further north, through Iran and Iraq.[3] With all the wars in that area, China apparently sees a need to have multiple alternate routes for trade. Good thinking in Beijing.
[1] https://en.wikipedia.org/wiki/Reconstruction_of_the_Karakora... [2] http://boi.gov.pk/userfiles1/file/List%20of%20MoUs.docx [3] http://www.xinhuanet.com/silkroad/english/index.htm