I made this suggestion in a reply to another topic. I didn't know if it would be seen, so here it is again: There should be an option to similar to "Move large files to end of drive during whole drive defrag" (on the Defrag tab) but for folders. There are certain folders that contain files that constantly change, e.g., "temp" folders and folders with antivirus definition files. If these folders could be specified, any files contained in these folders would be pushed to the end and would not get mixed in with the less frequently changed files. This would reduce refragmentation and subsequent runs of defraggler would be faster since it only has to defrag the files at the end of the drive.
I think this would be an excellent feature to reduce fragmentation of seldom changed files. There are certain folders that are constantly changing. For example, the "temp" folders in the user profile and in Windows, also, folders where antivirus definition files are stored. If the files in these folders could be moved to the end of the drive, as these files are deleted or replaced they would not be creating space between files that are seldom changed. With this feature, each time defraggler is run, the seldom changed files would not need to be moved and only the frequently changed files at the end of the drive would need to be defragmented.