Page 16-9 of the ippiman suggests that Inverse Quantization must be performed after calling ReconstructDCT...(). However, the documentation for ReconstructDCT...() states clearly that it performs inverse quantization.
I tried performing the additional InvQuant step while attempting to debug my problems with the AANTransposed functions and wow, they really screw up the output.
So I believe that the graphic on pg. 16-9 has an extraneous step inserted.