Leon got to the rail and there was room because they were so strung out. He had a spot and kept going. Irad and Mo almost ran into the rail at the start? Irad was on the rail too, but when they got to the second turn if you watch the replay there was a solid wall on the inside and Irad had a seam to get out behind for some room, but once he got in there he had to keep drifting out until he had a spot to straighten out. Leon was on the inside of that wall and there's a great move where he bulls between two horses to get back to the inside. But if you were behind the wall to begin with....

I think it was more the luck of how things broke than any deliberate "navigating." I don't think Irad could've done anything better or differently, he was inside all the way.