Taqwiyat al-ḥukm is not simply inserting a particle of emphasis. Certain predicate clauses highlight the predicative connection because their internal subject-predicate relation is itself related to an external subject.
زَيْدٌ قَامَ
Zayd stood up.
The verb contains an understood subject referring to Zayd, while the clause functions as the predicate of Zayd. These relations help explain the idea of a reinforced attribution. This must not be conflated with restriction (takhṣīṣ): strengthening an assertion and excluding other possible agents are different rhetorical operations.
Actual rhetorical force also depends on the conversational context and the purpose of the speaker.