Not sure why it didn't continue, it was one of those things that just got put to one side and never really picked up again.
The relationships thing never made it to the second prototype.. The first prototype did have it in, in fact here is a crazy picture which shows what happens if you were to turn the detail up to full in that version:
http://continuum.a-dot.co.uk/continuum.png
Not sure if that level of detail was very useful, but the idea was to try and explore the various relationships in the data. The detail sliders changed what information is shown based on domain experts prioritizing the data in each facet. We also did a bit of work into auto generating this priority rating, but that never made it into the prototype.
