So we see that Moody feels he owes James (Who would have thought that he was an Unspeakable) a life debt, and that is one of the reasons that he is helping Harry.
So with the other Unspeakables, Moody thinks that Harry and Hermione could be Unspeakables, or at least trained by them.
LoL... really, does Dumbledore really think Harry is that dumb to be treak when he don't want it to happen. Come on, he is no fool.
I'm happy that Harry and Hermione are going to become Unspeakables, that should really help them out a lot. Moody the old clow, using his peg-leg to do spells, nice work.