Especially since this year - Harry's fourth year, the Triwizard year - was the year that he escaped and began impersonating Mad-Eye. I thought it would be interesting if it was done the other way around here, with Moody capturing and impersonating Barty for a year, but given the assassination that's probably not what's happening... though I agree this may not be what it appears. But if it's not what it appears, I wonder what it is?