Is it possible that because he is using Ti secondarily instead of Fe (as an INFJ in Ni-Ti loop would), this seems to you as being NP? I've seen Ne types that lack this "openness" you're suggesting.
The part about the tertiary inflating itself is what I used to argue. But I don't see how that would look like NP. NT, yes. But the J/P is telling you the attitude of the iNtuition, so just adding Ni to Ti would not make the N look extraverted. However, I imagine looking at it from Jung's setup, starting with Evan as someone internally focused first (whichever functions he prefers), and then seeing that Thinking is dominant followed by intuition; I imagine it is possible for him to appear to be using the intuition internally as well.
What you're suggesting acknowledges that F seems to be below N and T. Inasmuch as I may have focused a lot on inflated puers until recently; I now realize that I had been caught up in a "hyper" interpretation of Beebe that tries to explain too much through function order. It seems that in actuality, the tertiary does not inflate itself to such an extent that a person
continuously appears to prefer the process over the first two. That I now believe has been exaggerated a bit. It happens probably in more brief instances. Like you'll see ENFP's get into brief spouts of organizing their space. And I know my Si is inflated a lot, and one may think I prefer it when I'm in a nostalgic mode; but it
overall still does not look like it is greater than T or N. (Like I probably show rather little of it here).
So T coupled with an internal focus seems to be what is prominent, followed by iNtuition, and Feeling appearing at times, it seems, like he said, that this is just something he has trained himself to do or learned by influence of others. It really does not
HAVE to fit into a particular "function order".
Perhaps "openness" wasn't the best word, or was too ambiguous. I don't want to say "warmth", as that is too easily misunderstood even moreso. But basically, what I'm referring to boils down to the directing/informing difference. Evan communicates more like informing types.