[NTG-context] Multiple text flows

Hi, My book needs to have two separate texts for two different audiences. I get the inspiration from http://books.google.co.in/books?id=qdltz8N9qSEC&lpg=PP1&dq=the%20body%20multiple&pg=PP1#v=onepage&q=&f=false. Here the author is separating each page on two parts. The top text is descriptive while lower text is literature research relating to the upper text. I want to have one text flowing on right page and another on left. However, they are interconnected i.e. parallel. So there needs to be an anchoring mechanism so that on each right-left page couple they are talking about the same thing. I am new to ConText but not shy of programming. I can explore any clues you give. Thanks, Salil