Speaking of MOS2, (molybdenum desulfide), here's an extract from NASA tests on what they have to say about it:.
''The "Snake Oil!" article refers to NASA Lewis Research Center tests that concern MoS2. The "Snake Oil!" article quotes NASA as follows: "In the types of bearing surface contact we have looked at, we have seen no benefit. In some cases we have seen detrimental effects. The solids in the oil tend to accumulate at the inlet, and they act as a dam, which simply blocks the oil from entering. Instead of helping, it is actually going to deprive that part of the lubricant."
MOS2 is in fact a very good lubricant BUT it is a solid mineral which insoluble and never dillutes into oil. It always remain a solid (very fine powder) with particules ranging from 2 to 10 microns. As with teflon, this material has the very bad habit of clogging small oil passages and accumulates in parts of the engine where oil flow is slower.
Here's some good reading:

http://www.vtr.org/maintain/oil-additives.html

JackD