The link you provided doesn't provide us with any insight into what the NSA's state-of-the-art might have been.
This NIST publication[1] says: "for ATA disk drives manufactured after 2001 (over 15 GB) clearing by overwriting the media once is adequate to protect the media from both keyboard and laboratory attack."
Tech changes have "altered previously held best practices regarding magnetic disk type storage media". It does not seem to confirm that multiple erases were unnecessary before.
This NIST publication[1] says: "for ATA disk drives manufactured after 2001 (over 15 GB) clearing by overwriting the media once is adequate to protect the media from both keyboard and laboratory attack."
Tech changes have "altered previously held best practices regarding magnetic disk type storage media". It does not seem to confirm that multiple erases were unnecessary before.
1: http://csrc.nist.gov/publications/nistpubs/800-88/NISTSP800-...