That shouldn't be a problem (as long as the vertices from all the unconnected meshes are selected and have the weights applied).
@Phillip: Well, looks like the main probleman is with the oars geometry. Because right now they are made with two unconnected meshes (each one).
Blender's Python console runs each line as soon as it's input, so you should paste the entire script (and press enter twice to ensure it's completed) only after doing all of the selection. Then it should be like the attached file.
I'm assuming that to run the script you just need to paste the code, select the tip's vertexes, go to the object mode and press enter to run the script, right?
Props aren't particularly good for performance - there's a constant cost for rendering each individual mesh (independent of the size or complexity of the meshes), especially if they're animated meshes, and I think it starts hurting once we have maybe hundreds of meshes on screen (whereas we can easily have hundreds of thousands of triangles), so using a hundred single-oar meshes for a single unit would be pretty bad.
What about we rig one oar and animate it. Them we can copy this oar as a prop of the ship.