Okay salvator94, so I tried your solution, and it does work. However, I lose the visual indicator bar window in Cinnamon which pops up when I adjust the brightness. Is it possible to have the best of both worlds, to so speak?
For instance, I still have the keyboard backlight brightness indicator bar window popping up with full functionality (can adjust brightness all the way down, all the way up for the keyboard backlight and do not lose the indicator window).
PS I also despise Ubuntu's desktop environment, though the support is good and the repositories are great. I think Unity was a huge, huge mistake, and I'm in the Linux Mint camp for good. According to distrowatch, I'm not alone!
I lost the indicator as well, but I don't care. It works. Battery life is a LOT longer with the display turned down.
Salvatore, I am curious, how did you find that solution?