For a new passage, work through these questions in order:
1. Are both units complete clauses, or merely parts of one clause?
2. Does each unit report, request, pray, confirm, or explain?
3. Is the second meant to share the first clause's syntactic position?
4. Is it reinforcing a claim or answering an implied question?
5. What unwanted partnership or change in meaning would inserting wāw create?
This keeps grammatical eligibility distinct from rhetorical suitability. It also establishes the criteria needed to study when clauses should be connected rather than separated.