There is no added value in repetition within two adjacent sentences.
"0 = All off" delivers the same message as "Please note: Setting the tonemapper to 0 will disable all types of tonemapping shaders."
Similarly, the "Look below to see which value has what effect." sentence is unnecessary when the values and descriptions are right below it and impossible to not notice.
Lastly, saying "there is no way to disable those effects individually" holds no value because it provides no solution, which goes against the purpose of fixboxes. The core of your contributions was retained after my edit.
The wiki is a community effort, so you, me, or anyone coming to correct is a part of what it is all about.