I believe ghost dust is too heavy for a ghost to manipulate. Remember how Agatha had to rip her arm off to move?
SHAZAM!!!! I think you got it, especially cause of bob's eye color!!!!!
Edit: Hold up... on second thought, I was thinking you ment he was in Dead Beat's time line, but that doesn't quite work... I'm a little wierded out here, but I think you might be on to something.
Maybe Harry's ghost dust with depleted uranium in it is too heavy to move when actually attached to a ghost, but I was thinking other types might just essentially make object solid to those of the ghostly world. Unlikely, but I was throwing it out there.
I like the idea that the entire situation at Mort's could be happening back during Dead Beat, after Cowl stole Bob, but before the darkhallow. It make some sense that the necromancers would have been ani-mort, though it seems like they would have had bigger things on their minds at the time. Of course, I haven't reread to check, but was there snow on the ground at the time? Also, it totally goes in the face of what Sir Stu said.
Finally, I like the discussion of this possibly being the book where Harry time-travels. After all, Harry is big on magic having to follow the rules of physics, and when you actually think of the physics of moving someone back in time (removing all that e=mc^2 from here to there) that would be staggering amounts of energy, but if he did it while a ghost, then there would be no movement of mass... It also ties into comments about spirits being able to view time differently, while mortal bodies have limitations.
