I can tell you why we decided to use 2X lacing on both sides for all of our builds.

By lacing 2X you increase the lateral stiffness and it also helps in transfer of torque a bit. With radial lacing on the NDS you also have no angle on the nipple, the spoke enters completely straight. With the lower tension and no angle this is where you can run into problems with NDS nipples loosening up as you ride (Reynolds is notorious for this as their NDS tension is specced at 25KgF)
http://www.reynoldscomposites.co.uk/...poke_chart.pdf

For us, 2X just makes more sense. The only drawback I can really see is that it's about 6 grams heavier due to the longer spoke length needed :-)