RAM in dual channel mode performs better than RAM in single channel mode, but you would have to run benchmarks to measure the impact. I'm not sure about the extent of the difference in the 3D modeling software scenario.

I remember seeing that article when it was posted on HN. The stencil alignment looks very intimidating and the entire process is obviously much more difficult than a SO-DIMM replacement, but it's good to know that upgrading soldered RAM may be possible in some cases for those willing to take on the challenge.