This doesn't change my point. Halliday and Matthiessen's analysis is one analysis of these phenomena. But if we can one minute assume that it is not the case that because they say something in IFG 3, then it must be true, then we can start getting back to doing real linguistics.As I said in my email, I believe an alternative analysis of this phenomena, where require/allow/permit, etc. are treated as full verbs, and since they have grammatical patternings very distinct to material verbs, to create a new process type for them.
 O'Donnell's point has no validity because it proceeds from an inaccurate rendering of the theory in question.
 For example, the verbs in these verbal groups are neither 'auxiliary' nor less than "full". In clauses such as 'I was required to leave', 'was required' is the alpha verbal group and 'to leave' is the beta verbal group in a verbal group complex.
 The distinct grammatical patterns reflect the fact that these verbs of modulation introduce causation into the clause by means of a verbal group complex, adding the feature of agency to the clause as a whole.
 Theory improvement proceeds from an accurate rendering of the theory in question. The issue is accurate interpretation, not dogmatic belief.