The firmware on the device is a black box that controls a more complex black box in an undocumented way and where errors can break it. You don't JUST swap the firmware out. Even so, he may have meant it in the context of the onboard software and modifiable hardware (eg switch they flip at factory to permanently set behavior). Sometimes a hardware engineer will call both firmware speaking shorthand. If it was the latter, you're unlikely to change it because they blow a physical fuse (antifuse?) inside the chip.
Some IP vendors are also offering encryption, tamper-sensing circuitry, and obfuscation to help chip-makers protect the systems better. They really want that extra few hundred dollars. ;)
Good thinking, you two! The link shows that the black magic (spindle control, etc) is in a dedicated chip controlled by another chip. The "black box" controlling the "black box." I thought they'd be on the same chip and software package. That would increase risk. I didn't anticipate them putting it on a dedicated chip. It makes sense along some lines.
So, that counts out at least one HD vendor from my claim. More could follow if they do something similar. Thanks for the article, too, as I enjoyed reading it.
Some IP vendors are also offering encryption, tamper-sensing circuitry, and obfuscation to help chip-makers protect the systems better. They really want that extra few hundred dollars. ;)