John his book vs. John's book : possession marking in English

The unusual development of the PDE [present-day English] s-genitive can be historically motivated, if the 's form is supposed to be not a mere leftover of the Old English (henceforth OE) casemarking, but the outcome of the merging of two patterns: the inflectional genitive ending (levelled to -s) and the construction "John his book" (henceforth 'possessive-linked genitive') during the Middle and the Early Modem English phases. As my corpus analysis will show, the semantic and syntactic constraints ruling the occurrence of the 's pattern in the time interval of the rise of the 's-pattern (1400 - 1650) are the same ones as those ruling the occurrence of the possessive-linked genitive. This hypothesis is further confirmed by cross-language comparison (with the other West Germanic languages, especially Afrikaans).