Bosch (the manufacturer of FUEL pumps) recommends a maximum scar level of 460. They don't care how you achieve it.
http://www.globaldenso.com/en/topics/091012-01/documents/common_position_paper.pdf
Since this recommendation did not come out until 2009 (ULSD came in about 2007) many people are unaware of it.
It seems that the ENGINE manufacturers are not presently concerned with the fact that diesel fuel in the United States doesn't meet the standards recommended by Bosch.
I'm not surprised that you did not need fuel additives for 30 years. Up until 2007 sulfur lubed your fuel system.
So don't be concerned, continue not adding lubrication to your fuel, your fuel pumps may not need it.