If there is no IPC improvement (how do you know?), it is not a marketing blunder-- I'm sure it was done on purpose in that case. Look at P4 Celeron. Why not compete? I suppose you can argue they should put a different label on the PR rating, like "C3000+" meaning, to be compared with P4 Celeron... OTOH, they can argue that "Athlon XP-M" is just such a label, and one cannot compare ratings between Athlon XP-M and Athlon 64 families. What can Intel say? Again, look at P4 Celeron GHz vs. P4 GHz. Same issue.
Doug