The above mentioned post is in reference to /loadhotkeys and /savehotkeys
Nothing at all related to keybinding to the best of my knowledge.
Of course I have been wrong before
the /savehotkeys hasn't worked for me either.
And with 12 characters, 9 of which are of each tradeskill class; its affecting my efficiency as you can imagine.
I sent a bug report and hope they fix it soon.
I would suggest you also send in a bug report if you also use the /savehotkeys command.