Martin (1992: 407):
Conversely, experiential meaning may be realised metaphorically with no necessary effect on conjunctive relations. Clause g-j in text [6:23] all have incongruent Subjects at the same time as temporal relations between the clauses are realised congruently as circumstantial phrases (i.e. setting in time: between 1937 and 1945, in the post-war years, by 1954-5).
[6:23] g Between 1937 and 1945 the value of industrial production almost doubled. h This increase was faster than otherwise would have occurred. i The momentum was maintained in the post-war years j and by 1954-5 the value of manufacturing output was three times that of 1944-5.
 From the perspective of SFL theory, there are no instances of conjunctive relations in the four clauses. There are, however, two instances of complexes related by paratactic extension (g, j), both realised by the conjunction and.
 To be clear, it is not the (interpersonal) Subjecthood of these elements that is incongruent, but the realisations of ideational meaning in the grammar: figure as nominal group (g, j), Process as Thing (h, i).
 The circumstances of Location: time do not realise temporal relations between clauses. As circumstances of Location, they each construe 'the location of the unfolding of the process in space–time' (Halliday & Matthiessen 2004: 265). A temporal relation between clauses in a clause complex is realised by a conjunction group. The cohesive conjunction of (groups of) messages is effected through conjunctive Adjuncts.
 In discussing grammatical metaphor, it is semantics (meaning) that is congruently or metaphorically realised in lexicogrammar (wording); so it theoretically inconsistent to couch this in terms of temporal relations between grammatical units (clauses). In discourse semantics, such temporal relations obtain between messages, the unit of the logical metafunction, whereas in SFL theory, they obtain between figures in a sequence.
 To be clear, this is shorthand for circumstances of Location (realised by prepositional phrases).