If it helps, here's a piece of information I didn't find out (i.e. David didn't tell me) until after completing the game the hard way: you can shoot the ghost to slow him down.

Let me say that again.

YOU CAN SHOOT THE YELLOW B*ST*RD.

The amount of revenge this lets me take on the Dust Hill A phantom in particular is well worth opening the level for. :P

D.F.