Halliday & Matthiessen (2014: 57):
The description of English grammar presented here is not designed as a reference grammar. However, unlike the recent reference grammars — or all previous ones for that matter, this description has been designed as one that can be used in text analysis — a task that imposes quite stringent demands on the description.
Cf the (self-promoting) misrepresentation of Systemic Functional grammar (and grammarians) by Martin & Rose in Working With Discourse: Meaning Beyond The Clause (2007: 1, 4):
In this book we are concerned with interpreting discourse by analysing it. For us this means treating discourse as more than words in clauses; we want to focus on meaning beyond the clause, on semantic resources that lead us from one clause to another as a text unfolds. … In a sense then this book is an invitation to grammarians to reconsider meaning in the clause from the perspective of meaning in texts; …
Grammarians are particularly interested in types of clauses and their elements. But texts are usually bigger than single clauses, so a discourse analyst has more to worry about than a grammarian (expanded horizons).Critiques of these and other misrepresentations can be found at the blog working with discourse.