When you switch to another mode (other than custom), the values become unadjustable because the presets (clear, standard, smooth) are used. The TV doesn't list what the preset values are, but the sliders retain the custom settings so you don't lose your personalized adjustments.
It wouldn't be a big deal to remember two values for the two settings, I suppose, but I believe that's why you still see those numbers. If you change to, say 8 and 2, you'll still see those custom settings when you use the other presets.
The other menus are identical, so if you have a custom setting for your picture settings (brightness, contrast, etc), then those values will remain as you set them in custom, even if you go back to "Dynamic, Standard, Movie, etc".
Does that help?
I noticed recently that no matter if you choose 240hz clear/standard/smooth setting they all have judder as 5 and blur as 5. But if you change them in custom and then go to those other modes it stays as the custom values. Not sure there is a change or not. When the AMP is set as clear/standard/smooth, should the sliders display the corresponding value for that particular setting or not?