Sounds like it would be better suited for the late, lamented Wiki.
I wonder if we're ever going to get that back.
Until then, I think there are too many functions to add a sub-category for each one (and new functions are added with each version). I would prefer a Subject heading that included the function and some prefix text to aid the Search function, say... "EXPLAIN <3D function name> USAGE", followed by a descriptor for the basic problem.
TC Pro Platinum 2017, 2016 & 2015 (all with LightWorks) & V21
System: i7-5820K @ 3.30GHz, ASRock X99 Extreme4, 16GB DDR4-2133 RAM, Gigabyte GTX 970, Samsung NVMe SSD 950 (256GB), Windows 7 Pro (64-bit) SP1