You might do a regular internet search and see if any one else had good results with it.
I general I thank that anything that would thicken the oil (STP comes to mind) would tend to reduce blow by (but probagbly not the blow by comming from the exhaust valve stem area). a.k.a.: viscosity index improver. Probably less effective on diesels than gassers due to the diesels higher operating pressures.