How should possibility be distinguished from a verified defect in differing chains?

The Meeting Condition in Muʿanʿan Hadith: Muslim’s Rejoinder and Route Comparison

• A conceivable intermediary does not prove a break; case-specific evidence is needed
• A longer chain always proves closer direct hearing
• Every chain for the same text must be assessed in isolation
• Corroboration and explicit hearing are irrelevant to hadith criticism