I apologize for bump the old topic, but I have some interesting observations that I would like to share, maybe this will help someone in the future because once I was on the lookout for useful advice.The nano technology is a benefit in so far as it is chemically inert and unlike the historic friction modifiers of old that used chemistry (Zinc and Sulphur) and temperature to activate, the new types work in much the same way as older solid suspensions of EP oil additive by coating onto the surface to create a lower friction layer. Typically oils would have a fatty acids to reduce friction on start up, whilst AW or Anti-Wear (ZDDP or Zinc DialkylDithioPhosphate) would be used for metal-to-metal contact at higher contact temperatures, and for extreme loading and very high contact temperatures, EP in the form of Sulphur-Phosphor (which you can smell the odour of easily) was used. But EP oils can attack Copper and copper based alloys so solids of Molybdenum DiSulphide, Graphite or even PTFE(Teflon) are used in alternative cases in gear oils.
Engines historically used AW with no need for EP, but owing to the restriction on metals because of the Cat exhaust and the environmental pressure, Zinc and Sulphur have been reduced to a large degree in oils, although ZDDP is still partly there to counter corrosion and oil oxidation. Engine oils, particularly diesel, also have alkaline detergent packs that help neutralise Sulphuric acid formation in the sump from water and Sulphur in the fuel mixing following fuel dilution. This is more a concern on diesels, though.
Of course, on an engine this is only necessary during a start as normally the majority of the components are separated by a film of oil so the base oil quality is equally important in ensuring that the most susceptible parts such as the soft bearing shells are not in contact with the opposing component. No additive will improve the film strength of the oil as such except increase it's viscosity and then you start suffering efficiency losses owing to the increased drag of a thicker oil. Synthetic base oils have a greater film strength than mineral and semi-synthetic oils at an equivalent viscosity grade so can maintain the film despite being thinner.
Consequently a high quality oil is actually a compromise that must allow the additives to do their job without interfering with each other. Adding chemicals will upset that balance but likewise adding physically inert suspensions can lead to these being trapped in the filter or worse collecting in fine oil ways and choking the flow. There is absolutely no need for friction modifiers in an engine once it is running.
Any demonstrations of the chemical type of additives (like some types of Lucas) https://mechanicguides.com/best-oil-additive/
should be taken with a pinch of salt. The classic demonstration using a Timken OK load test rig with lever is fundamentally flawed. The demonstration shows that with standard engine oil the lever can manage three weights before the test rig grinds to a halt and scarring occurs on the test piece. With the chemically active substances, what in effect happens is the metal softens to reduce friction and thus a much greater number of weights can be added, but the fact that scarring has disappeared is due to the metal softening and flowing with the result that the surface now appears smooth. What has happened though is that the profile has changed and this would lead to improper clearance and lots of backlash noise on a gear set. In addition, there is no where on an engine that would encounter such a level of metal-to-metal contact loading so there is no need otherwise the oil companies would have added something to the oil to protect the engine.
Finally, with any f these additives, ask the supplier if they have an independent research study to back up the claim, and secondly if they have an MSDS. Some of the additives are chlorinated material (hair shampoo and milk can achieve the same results!) but the chlorinated material on mixing with moisture in the sump (condensation etc.) can produce PCBs which are damaging to the nervous system.