293ff.) a) that intraposition is GENERALLY marked for NRIs/CPs and requires intonational breaks before and after the infinitival complement, and b) that extraposition is a gradient notion (the bigger a complement, the more likely it is to extrapose), but in principle also possible for vP/TP and VP.
5: (i) extraposition is a gradient notion (the bigger a complement, the more likely it is to extrapose), but in principle also possible for vP/TP and VP; (ii) intraposition is generally marked for NRIs/CPs and requires intonational breaks before and after the infinitival complement.
The gradience claimed by (i) is supposed to cover the entire range of infinitival complements--from FRIs, whose VP complements do not extrapose at all, through (L)RIs and RNRIs to NRIs, whose CP complements are preferrably extraposed, cf.
First, there is a strong tendency not to extrapose if the predicate is discourse-new.
Deixis, anaphore et cataphore dans les constructions extraposees. In L'ordre des mots II, domaine anglais, 253-279.