Martin (1992: 120):
The network contrasts the [neutralised] reference of little texts with that in registers where deixis is fully effected; then [effected] reference is broken down into [generalised] reference to no one in particular and [specified] reference to classes or participants or their members. The feature [specified] open [sic] up options in three simultaneous systems: the [generic/specific] opposition, the [presenting/presuming] opposition which makes reminding phoricity available and the [comparison/–] one which opens up the possibility of relevance phoricity as well. Then a breakdown is provided for [presuming] reference leading through the features [variable], [nominal] and [undirected] to the possibility of presuming a superset, invoking relevance phoricity once again.
Since proper names and pronouns are not modified with comparative adjectives or quantifiers in English, the feature comparison cannot be co-selected with them. The I/T superscript notation blocks this combination.
For the theoretical misunderstandings and internal inconsistencies that invalidate this network, see the critiques of this chapter here. Note that the network provides no realisation statements that specify how these features are realised syntagmatically, or lexicogrammatically.