Martin (1992: 262):
A number of passages from [4:2] will be reviewed; some of these were commented on in 4.1 above because they cause problems for the clause complex analysis, in spite of the fact that Halliday's system was specifically designed to handle the dynamics of clause combining.
The passages that were commented on (1992: 162-3) were not clause complexes, but clause simplexes involving cohesion, and so do not "cause problems for the clause complex analysis". Of the four, only one involved a conjunctive relation; the other three deployed demonstrative reference. See previous critiques here and here.