I think a big factor in what causes some clothing to stand out more than others, regardless of camo pattern is contrast. Many of the newer fabrics are very reflective of light, smooth and sometimes shiny fabric. Contrast that with fabrics such as wool and fleece, which are much softer, do not shine in any light, and are also much quieter. Many of the new dyes used to combat fading are so bright they simply don't blend as well, and thus reflect more light.
3D camo seems to help because the surface is not flat, this it breaks up the prolem with refectivity as well as helping to break upyou outline.
I wash all my hunting clothes with sprt wash or with just plain water and baking soda so as to not add any brighteners or artificial scent to them.