Those Straits are tight...both should not have been transitting at the same time. Maybe the sub was on patrol. Either way, major screw up.
Oh c'mon. I know you like to think of yourself as an expert on naval matters but now we're getting into stupid. Have you ever transited the Straits of Hormuz? I have, quite a few times, and because of my job I was the one who laid the track we used. They are plenty wide and plenty deep. It's a stressful transit due to the sheer amount of shipping traffic but the Traffic Separation Scheme keeps everyone on a fairly predictable track. As far as the navigation (keeping the ship in safe water) goes it is a piece of cake.