re: WWII aficionados- were PT boats an effective part of the war effort?

The Japanese nickname for the PT boat was devil boat so I think that in itself ought to let you know how effective they were. A lot of people get this glamorous image of them charging at a Japanese capital ship zigzagging through waterspouts of gunfire and firing torpedos but some of their most effective work was sinking Japanese transport barges and landing craft that were used to reinforce their island garrisons.