I do not have a Recovery Partition on the MBPro HD, so cannot speak to that.
HOWEVER, I made a spare/backup "Install Thumb Drive" of Sierra from the download before installing Sierra on the MBPro. When I reboot in Recovery Mode with the thumb drive, the DU gives the option to erase/secure erase anything that is mounted - internal and external - including the originally installed HD never removed from my MBPro.
P.S. This is getting a bit away from the original WIDGET question. Should a new thread be started? Or simply end this sideline at this point?
If you're running Sierra you've got a recovery partition, but it doesn't show in an option boot; you've got to do a command-R boot to reach it, and I imagine it will allow a secure erase if your thumb drive does.
It sounds like your recovery partition is recognizing that you're running a HDD rather than a SSD.
(Maybe the Mods can detach the last bunch of posts that pertain to this matter and start a new thread with them.)
