Taxis Vs Embedding

Halliday & Matthiessen (2004: 426):

It is important to distinguish between the 'tactic' relations of parataxis and hypotaxis on the one hand and embedding on the other.  Whereas parataxis and hypotaxis are relations between clauses (or other ranking elements), embedding is not.  Embedding is a semogenic mechanism whereby a clause or phrase comes to function as a constituent within the structure of a group, which itself is a constituent of a clause … .  The embedded clause functions in the structure of the group, and the group functions in the structure of the clause.

The distinction between hypotactic and embedded expansions is set out in Halliday & Matthiessen (2004: 442) in Table 7(15).

What Is The Advantage Of Distinguishing Between Embedding And Hypotaxis?

In the case of projection, it lays the foundation for the semantic distinction between (pre-projected) facts and (projected) reports (Halliday & Matthiessen 1999: 28).

Meaning "Beyond" The Clause

In SFL theory, the two enabling metafunctions, the logical and the textual, provide the means of realising meaning "beyond" the clause.

The logical metafunction does this structurally, by relating clauses in complexes by means of interdependency and the logico-semantic relations of expansion and projection.

The textual metafunction does this non-structurally, through the cohesive relations of reference, substitution–&–ellipsis, conjunction and lexical cohesion.

Anyone who claims that the grammatics does not model meaning "beyond" the clause does not understand the theory (or is being dishonest).