Just a quick follow up. I mounted all my DrivePool drives into a mount folder as you suggested, and it did indeed solve the issue of being able to catalog each drive. I had been trying to figure out a solution to that problem for a couple of years, and your method is easy to implement, and it works. Thank you very much for that suggestion.
Instead of assigning drive letters to your 20 USB disks, you could mount them in a folder. This means that the disks can be accessed individually at any time to catalogue or check their content, but they don't clutter up Windows File Explorer (since they appear as subfolders of the C: drive). You can also CHKDSK the individual disks if needed. I have set up my drive pool in this way, although I have only 4 USB disks in the pool:
C:\Mount\Pool_1
C:\Mount\Pool_2
C:\Mount\Pool_3
C:\Mount\Pool_4
You specify the mount point on the Windows panel where you assign drive letters.
-- from CyberSimian in the UK