Honestly, I think he can do it. With the amount of times he's run the steeple and how quickly he is progressing, I think taking 6 more seconds off is very possible for him, especially since he's still only 23...gives him probably 4 or 5 more years of very high level running, until his speed starts to decline and by then he will probably have moved up in distance and be back to a 5k/occasional 10k guy. I could see him in the end with maybe a high 7:58/low 7:59 PR.