[s_fischer]

I'm not even remotely qualified on anything ship related so my question might be totally pointless.

But by your logic, couldn't one argue that reaction time plays a rather large role? If you are navigating a narrow canal with thin margins for error, wouldn't you need good timing to start a manuever at a certain point so that the ship is able to respond by the time that you need to truly adjust it's position? If some sort of weather event/anomaly caused an unexpected change of course, wouldn't reaction time be even more critical because you have less time to make a correction if you don't act immediately?

[why_Mr_Anderson]

What I was trying to say was that even if the captain instantly tried to reverse the course, ship has already started to move and due to size its momentum is enormous.