I honestly can't see how the XP defragmenter does a better job as I check with the windows defrag, analyse to check if it needs defragmenting I run Power Defragmenter, if I check after it is complete (Very Quick) it shows zero fragmentation. So I can't see how you can get better than zero fragmentation.
The time taken to defragment a disk with XP's defragmenter I could almost etch the contents of the disk in stone, a slight exaggeration I know, but like if too short for the XP defrag.