The connection between the healing of the paralytic and the teaching on the mountain is not a guaranteed standardization; the window of understanding is narrow and closes quickly.
The capital is finite, and the crowd's attention is a diminishing resource.
If the audience focuses solely on the physical miracle, the spiritual significance of forgiveness may be missed, making the impact on the teaching marginal.
For example, if people only remember that Jesus can heal, they miss the deeper idea of the Law and the Kingdom of God, which weakens the connection.