Consider two reliable non-mudallis transmitters whose dates and circumstances make meeting genuinely possible, but no actual meeting is documented.
On Muslim’s criterion: Their link may be treated as apparently connected absent credible counter-evidence.
On the established-meeting criterion: Further evidence that they met or that some hearing occurred is required.
On either approach: If their dates show that the claimed teacher died before the student was born, the link cannot be direct.
This is a disagreement about the evidentiary threshold for the link, not a final ruling on every report in which it appears.
A further application: “X told me that Y said ...” explicitly affirms hearing **from X**, but the link from X to Y expressed by *anna* is a separate question. The majority assesses it as with ʿan, subject to the continuity conditions; Aḥmad, Yaʿqūb ibn Shaybah, and al-Bardījī do not automatically grant *anna* the same connective force.