Fawcett's Argument Against 'Adjectival' And 'Adverbial' Groups

Fawcett (2010: 206n):

¹¹ In some earlier systemic grammars the concept of 'adjectival' and 'adverbial' groups was explored. But the fact is that the system network of meanings and the elements of structure in syntax that it is necessary to set up to handle the type of 'quality group' with an adjective at its apex includes essentially the same types of meaning and structure that are needed for the type with a manner adverb at its apex. It is therefore appropriate to capture this significant overlap by modelling the two phenomena in the same system network and the same syntactic unit. Compare He is less slow than he used to be and He climbed the stairs less slowly than he used to climb them.

Blogger Comments:

[1] This is misleading, since the adverbial group is a class of group in SFL Theory. 

[2] To be clear, Fawcett does not provide any system network of meanings to validate his claims.

[3] To be clear, Fawcett argues for the theoretical validity of his quality group on the basis of both meaning and structure. And from the perspective of SFL Theory, in terms of meaning, both variants — adjectival and adverbial — do realise the same meaning, a quality, and in terms of structure, both variants do share the same logical structure:

However, what Fawcett's quality group fails to account for is the fact that the semantic element, quality, is realised as a different grammatical element in each case: Attribute (participant) vs Manner (circumstance). In SFL Theory, this distinction is "predicted" by the fact that the 'quality-as-participant' is realised by a nominal group, whereas the 'quality-as-circumstance' is realised by an adverbial group.