Dryer (1980): "... these tendencies [ki ez kokatu perpaus osagarria an erdia e esaldia] are due to the processing difficulty presented by centre-embedded sentential NP's: such sentential NP's interrupt processing of the main clause."

Gogora gaitezen nóla Dryer-ek (an bere "The positional tendencies of sentential noun phrases in universal grammar", 1980:126) zúen zehazten honako tendentzia posizional universala an kokapena e perpaus subordinatu nominalak (konpletiboak): 

Sentential NP Position Hierarchy

clause-final position > clause initial position > clause-internal position

Dryer-ek dio ze (1980:168):

... I accept the explanation offered by Grosu and Thompson discussed in 3.1.4.1., namely, that these tendencies [beheko aipuko 109 eta 110 tendentziak] are due to the processing difficulty presented by centre-embedded sentential NP's: such sentential NP's interrupt processing of the main clause. [Dryer, 1980:168]

Hortaz, halako perpaus konpletiboak joko lukete ki ez agertu an erdia e esaldia zeren posizio horretan oztopatuko lukete a prozesamendu jarraitua e esaldi nagusia, zeinen kodifikazio-deskodifikazioa geldituko litzaké etendua (eráginez kostuak an lan-memoria eta eráginez kostu interpretatibo-expresiboak).