Here is the Matt 3
15 ἀποκριθεὶς δὲ ὁ Ἰησοῦς εἶπεν πρὸς αὐτόν, Ἄφες ἄρτι, οὕτως γὰρ πρέπον ἐστὶν ἡμῖν πληρῶσαι πᾶσαν δικαιοσύνην. τότε ἀφίησιν αὐτόν
. 16 βαπτισθεὶς δὲ ὁ Ἰησοῦς εὐθὺς ἀνέβη ἀπὸ τοῦ ὕδατος
τότε adv. then, at that time... What happens after their discussion...
Then, at that time, John permits
This is, in my model, a very common, vanilla usage of the Present Tense in Narrative.
3.16 After Jesus was baptized (note Matt begins to develop another contextually based DC/C, showing the temporal elements)
Stephen, I don't think our models are convertible. If you are saying that the contextually based Present Tense in Model B (the one I subscribe to) can mean the same as the HP in Model A (the one you subscribe to), I just don't see how. I think you would then have to adopt the Historical Aorist, Historical Perfect, and the Historical Future, not just the HP. And I am not sure how you would explain a HP in light of the entire book. However, let me be quick to add that I feel you are moving in the right direction, and I'm not implying you've made some significant change in your thinking based on our exchanges. We still retain our different, and I would say non-convertible, models.
That the Present Tense of ἀφίησιν in Matt 3.15 seems so natural within my model, it was hard to see why you would use this HP as a difficult tense usage. I understand in your model it does, but it is just natural in mine. I think the "thinking" within each model is noticeable different.
Shall we continue to beat these two dead horses?