Lets make Lightmass EPIC (and understandable)

If you take good care while modelling, then you don’t need to tweak ini values in 4.11. But, in very rare case for very large environments to remove few artifacts you may have to fiddle with ini values

With regard to changing values in ini, Yes, you need to change the corresponding settings i.e., if you are using Medium quality for light building, you need to change values under Medium settings in ini