Deform mesh verticies not working

Gudday,
Can anyone help with a problem with deform laticess? I am doing the (really great) dolphin tutorial from BlenderNation. I have found the mesh will deform in the front view but when I get to the top view, only 2 verticies of the 3 vertice lattice will have any effect on my mesh. The other will move just fine but does not seem to have a parent relationship with the mesh.
What gives? can anyone help?

Ta
:confused:

Pictures? Link to the tut?