Sure Jesse. This is from what I know, and in no means am I an expert at this.
If you imagine how the laser cures each layer, when it hits the resin (although this is happening very fast), it creates a dot on the surface of resin. The pigment, or photoblockers, stop the light (UV light in this case) of the laser from penetrating past the layer thickness (50 microns lets say), and also they stop the light from bleeding to the sides from the hitting spot of the laser. When there is not enough pigment or blockers, after your initial layer cures, there is residual curing past that layer, so the next layer is already partially cured, so you can get roughness and loss of detail. You do need some of that residual curing, so that layers stick to each other, but if there is too much you get blurring of details, and bumpiness from over-cured resin. So it's combination of enough light blocking pigment and lower viscosity that can create a higher resolution print.
So obviously if you want really high resolution for jewelry or highly detailed prints, it's important to have enough pigment, to stop the light from bleeding through and over-curing past the layer thickness and also to the sides of the dot.
Ultimately I think Form Labs needs to make different resins for different purposes (castable, rigid, flexible, high resolution, etc) , and also, I don't think it's a good idea to have the same resin for different layer thicknesses. Because for example, the 25 micron setting would need more pigment and higher viscosity than the 50 micron print, or the 100 micron print. Each resin should be optimized for a specific layer thickness and resolution.