Pertaining to the User Preferences AND Theme Settings therein

Where is there a reference to what all of the Theme color settings affect. I have found by Trial and error some and some are clearly labeled, but many are WTH? Also where is there an uptodate explanation of the settings in the other tabs, like System etc…? The online description in the manual
Open GL

Clip AlphaClip alpha below this threshold in the 3D viewport. Minimum: 0.000 (No Clip) , Maximum: 1.000 , Default 0.000 (No Clip)MipmapsScale textures for 3D view using mipmap filtering. This increases display quality, but uses more memory.GPU MipMap GenerationGenerate MipMaps on the GPU. Offloads the CPU Mimpap generation to the GPU.16 Bit Float TexturesEnables the use of 16 Bit per component Texture Images (Floating point Images).Anisotropic FilteringSet the level of anisotropic filtering. Available Options are: Off’’ (No Filtering) , 2x (Default) , 4x , 8x , 16x
Window Draw Method

doesn’t explain why or why not to set any of these in any manner, and/or what is the advantage of the default etc. ?