Correct. You'll have to experiment a bit since all sets are different but this is a good starting point.This is just for the luminance setting, right?
I saw your post about deep water horizon but I don't own that film. It's tough to use content to set brightness only because every transfer is slightly different and then you have directors intent to worry about. Some films just have muddier blacks...like Star Trek beyond. Other films have great blacks like Underworld.
Try multiple titles that you are familiar with and that'll help you set it right. And, once it's set and looks good for most content, leave it. A few titles will always appear off but just let it be. Get it set where it works for most of what you watch and you'll be good.