The /SUBDIR (subdirectory) tag comes from the default in Advanced File Selections. (include subdirectories is selected by default)
From you example, you can tell that someone created the job and first selected the entire D: drive for backup. From there, the user then specifically selected the D:\Oude disk directory and from AFS selected to Exclude that directory (including all of it's subdirectories since the initial D: selection would have grabbed the subdirectories had they not been included in the exclude order. Finally, the user then selected the D:\appl directory again for inclusion in the job (meaning they deselected it, then reselected it)
The reason not all of D:\*.* is being backed up is specifically the /EXCLUDE selection. Anything marked as exclude will be taken out of the backup selections.
As noted above, it would appear the user deselected and then reselected the D:\Appl directory. It would be backed up by the D\*.* selection anyways so it will be skipped by the job as simply being redundant. (it will be backed up already by the first D\*.* so it will not be backed up twice by the job)
