Role As Identifier Value

Interpersonal Metaphor And Discontinuous Subject

he	is	less likely [ than Ivy ]	[[ to have spoken ]]
Sub-	Finite	Complement	-ject
Mo-		Residue	-od

cf he having spoken is less likely than Ivy (having done so).

Cf the Cardiff Grammar analysis (Fawcett 2007: 934):

he	is	less likely than Ivy	to	have	spoken
Subject	Operator/Auxiliary	Auxiliary Extension	Infinitive	Auxiliary	Main Verb

That is, Fawcett analyses 'spoken' as the Main Verb of this attributive clause, and 'is' and 'have' as two of its Auxiliaries.

Predicated Theme Vs Postposed Subject

it	‘s	your good luck	that	nobody	noticed
Sub-	Finite	Complement	-ject
Identi…	Process	Identifier	…fied

Ambiguously:

(a) Predicated Theme (agnate to nobody noticed your good luck)

it	‘s	your good luck	that	nobody	noticed
Theme: predicated			Rheme

(b) Postposed Subject (agnate to the fact that nobody noticed is your good luck)

it	‘s	your good luck	that	nobody	noticed
Theme	Rheme		Afterthought

See Halliday & Matthiessen (2004: 97-8).