Using measures data inside "Formattng settings"

I think with a matrix data view, you're confined to the row/column/cell combination for each data point and probably can't do much to change or manipulate the grain.

I know that Charticulator had some data modelling instructions  for ensuring a degree of compatibility to the web app (which had a main dataset and one for node relationships), but this uses the categorical mapping, so I'm not sure if you could get simialr results, but could be worth a look.