The actual correct destruction method is as follows:
1. For floppy disks, remove the plastic covering and shred the disk. It's highly recommended that you use the bulk eraser prior to shredding the disk.
2. For hard drives, bulk eraser multiple times, followed by destruction of the drive. It's been a while since I saw the video, but literally tearing the drive apart is required.
FWIW, I was never in the DoD, I did some short contractor work and was required to watch a video on the proper discard of storage devices. It was a really bad imitation of Bill Nye for DoD types.