Hello Mark,
The fundamental reason for which the nodes are duplicated is to recognize & capture the instance specific properties of the multiple instances of the subassemblies. Instance properties are like hidden or suppressed.
By the way we are updating the page you have mentioned & will let you know.
Meanwhile, you may please use the fact in your application that whenever in the document section filepath attribute is same then it indicates presence of another instance of the same sub-assembly.
Please let me know if you need any further clarification,
With best regards,
Amol
