In a standard batch environment, you might set the NAFILE=nafile.dat. However, if two instances of the application tried to run simultaneously - as can occur under Docupresentment - there would be a clash over that file and one or both runs would get messed up. So the idea of substituting the GUID names on such files is to prevent those classes between processes under Docupresentment control. I suppose creating a separate data subdirectory per process would do the same thing, but then you would have lots of subdirectories that need to be cleaned up at some point. You would have just as many files as before, but now with more subdirectories. So do you have some goal other than to have each process run using a different data directory? What is it that you are really trying to solve?
I understand that I would have just as many files.
For troubleshooting purposes, I find it would be easier to find what I need.