Old Spanish clitics or weak pronominals differ from modern Romance clitics in their syntactic properties. They are NP's or PP's, share the distribution of other phrasal complements, and undergo the same movement rules.
In Old Spanish (ca. 1200–1450), weak pronominals encliticize in Phonetic Form, after syntactic and stylistic rules have applied; i.e. they are phonological clitics.
In doubling constructions, including the resumptive pronoun strategy, the pronominal/clitic is the phrase in Argument-position; the doubling phrase is a topic or focus constituent, base-generated as a left or right adjunct of one of the maximal projections (i.e. VP, S, S′, S″).