In this answer:
regarding substituting for quinoa flour, the answered alleges that another so-called "medium" flour can be substituted.
When I googled, I found that so-called "light flours" were alleged to be high in starch; rice flour or glutinous rice flour was the usual example. I found far less consistency—and no definition based on an objective criteria—for medium and heavy flours, although nut flours usually seemed to be grouped as a heavy flour. Almost all references to these terms were from the gluten free community.
Is there an actual objective criterion for these categories of light, medium, and heavy flours? If so, what is it, and what does it mean for their baking characteristics? Is it just a cultural thing in the gluten free community to group together empirical experiences?