وإن كان مظهرا فليس إلا للتقوي، وإن كان مضمرا فقد يكون للتقوي، وقد يكون للتخصيص
If the subject is an explicit noun, the cited account assigns it reinforcement only; if it is a pronoun, reinforcement or restriction may be intended.
This is a particular formulation within the dispute, not a rule accepted without qualification. The contrast concerns the fronting of an overt noun such as «زيد» and a pronoun such as «أنا» or «هو».
An immediate objection is why pronouns should have an exclusive claim to restriction. Might an explicit subject, in a suitable contrastive situation, also convey it? The section examines this problem rather than suppressing it.