That explains the perfect blacks of the mooring posts. Were you bracketing around Tri-X at box speed. This looks like at least 3200 grain or maybe more? 6400. Either way, a very cool effect. I foresee some attempts to imitate in my future using the Arista Premium 400 I ordered a few days ago.
the grain primarily comes from the lith developer/paper combination. Diafine gives fairly smooth grain even when you use TriX at the recommended speed (for Diafine ) of 1600 although I shoot it at 1250 to make sure I get enough shadow detail.