Subject-verb order in Tumzabt

Going through Brahim and Bekir Abdessalam's brief grammar of Tumzabt Berber (الوجيز في قواعد الكتابة والنحو الأمازيغية "المزابية": الجزء الأول) recently, I was struck by their discussion of the problem of subject-verb order. Berber in general allows both verb-subject and subject-verb order, with the case ("state") of the subject depending on which order is used. Determining which order is used under which circumstances, however, poses some difficulties; the same language may be described as VSO or SVO, depending on who you ask, and the determining factors certainly differ from one variety to another (cf. eg Mettouchi fc for Kabyle). Their take on the problem combines information structure with pragmatics and verbal mood. The latter two factors can very likely be reduced to information structure too, but that would require testing; in any case, the observation that VS order is required for serialization is interesting. Here's what they had to say, translated into English (pp. 129-130):

We observe that in the first set of examples, the subject precedes the verb; this is the usual form in an Amazigh clause consisting of a verb and a subject.

In the second set of examples, the subject follows the verb. This happens in the following cases:

1. The subject may follow the verb when it is specific and known to the speaker and listener because there is a connection between speaking of it and a previous expression involving speaking of the same subject. For instance:

   twelleh! afunas-nni yetthaḍa - Watch out, that bull rampages.

   After the two parties have parted, they meet again the next day, and one says to the other:
   yak yhaḍ ufunas ay-tessečned asennaṭṭ! - Indeed that bull you showed me yesterday really did rampage!

   Here, the subject - the bull - is specific for both parties to the conversation in the second usage, since it had been spoken of earlier.

2. For the sake of irony, which can only be deduced from the context surrounding this expression and from the circumstances of discourse, eg if we say:

   tiɣawsiwin-ess tqimant-edd ɣel wezğen, drus mi yefra igget, ay-tinid : yebṛem werğaz ! - His affairs stay half-done, rarely does he resolve even one, and you tell me: he's a careful man!

3. The subject may follow the verb obligatorily in the serial aorist, eg:

   yuli tazdayt yuḍa-y-as wemjer - He climbed the date palm and the sickle fell from him [and dropped the sickle].

   It may also occur directly following the verb in the future tense aorist, eg:

   ad tatef teğrest ad yireḍ isemmuṛa n tḍuft or tağrest ad tatef ad yireḍ isemmuṛa n tḍuft - When winter comes, woolen clothes are worn.

They follow this up with an observation that seems quite astonishing from a comparative Berber perspective (p. 131):

A subject following the verb is put in the construct state if definite, this being the normal case for the postverbal subject, and is put in the free state if indefinite without any need for the [indefinite] article iggen / igget ["one"].

Unfortunately, they provide no examples to illustrate this claim.