DiskWarrior and Speed Disk oddity

Francis Drake writes: "I've observed an odd but apparently innocuous behavior when using Alsoft DiskWarrior 1.0.2 and Norton Speed Disk: After I defragment a disk, using Speed Disk 4.0, DiskWarrior reports directory damage ('The original directory is damaged and it was necessary to scavenge the directory to find file and folder data·'). No other utility confirms this so-called damage and there's never anything obviously wrong about how the partition in question behaves.

Update: Alsoft's Joe Muscara replies: "After a disk is completely defragmented, the extents tree of the disk directory should contain no extent (fragmentation) data. Norton Speed Disk incorrectly leaves data in the extent tree. Other disk optimizers and the Mac OS properly remove unneeded extent data. Speed Disk does mark the extent data as unused, but leaves the data present.

DiskWarrior's unprecedented repair ability is partially a result of its focus on directory data rather than the directory structure. As previously noted, Speed Disk did correctly update the directory structure of the extent tree, but left the unneeded extent data. DiskWarrior assumes the directory structure is damaged when it conflicts with the directory data found. This conflict resulted in the damaged directory message from DiskWarrior. Ultimately, in this case, DiskWarrior creates a new directory with an extents tree that does not contain the unneeded extent data."