Further evidence that Jesus' conversation with Nicodemus ends with John 3:12

Below is John 3:1-21, traditionally considered together as a single "Jesus and Nicodemus" pericope. I have highlighted all first- and second-person pronouns and all occurrences of the verbs say, tell, speak, and answer.

Doesn't this make it easy to tell at a glance where the reported dialogue ends and the author's commentary begins? The dividing line is between vv. 12 and 13, the same point I had previously identified, based on entirely different textual evidence, in this post.