Daverobert, Cedric,
Yes, the ferry would have easily avoided a ship that had been drifting for some time. The point is that the near-accident happened because Baltic Bright suffered a full power failure while crossing the ferry's bow. Having another ship slow suddenly and turn toward you while crossing your bow makes for a "suddenly interesting" bridge watch. It appears that the crew of Silja Serenade reacted well to a normal situation suddenly gone bad.
"The cargo vessel had first intersected the course of the ferry from the left at a normal distance. Soon after that, the Baltic Bright lost electric power and with the blackout, the ship also lost its steering. Soon after that, the freighter turned 180 degrees, coming directly into the path of the Silja Serenade. The Silja Line vessel managed to avert a collision by putting its engines into reverse".(Helsingin Sanomat)
----------------
Best,
Charles