Retrospect writes the files contiguously when it does the backup. Then writes them contiguously when you restore. If your disk is highly fragmented the backup takes a lot longer than the restore because it is reading them from their various locations on your disc and writing them in one piece to the backup. I have found that the Retrospect strategy is hours and hours faster than Plus Optimizer (Which is all I have nowadays). Though both can run unattended. But your point that many mistakenly believe disc de-fragmentation is unnecessary in OS X is certainly true. The recommended disc format of OS X is identical to OS 9 - HFS Plus. It needs periodic de-fragmentation to perform at top efficiency. > Amazing, so Retrospect goes through say, a 20 GB drive's worth of > fragmented files and does what? It moves each non-contiguous file > into what open drive blocks to get them in a contiguous state? Is it > faster than Speed Disk?