A technical difference concerns whether a common respect drawn from multiple actual sensory elements is enough for tamthīl, or whether a narrower description involving an imagined or conceptual composite is required. The broad formulation treats extraction from multiple elements as central, while the treatment associated with al-Sakkākī places a further restriction on this class.
This difference can change the classification of some examples. Battlefield dust and flashing swords readily form an integrated scene under a broad understanding, while a more restrictive framework may require a special non-literal configuration.
Keep the terminological criterion separate from the factual structure of the example. That makes it possible to understand the disagreement without misdescribing the image itself.