Recently I have been using one of my modifiers with great success and feel many would benefit from this information. To get the finest detail to print, I have always been using loose ink that was just ready to cause tinting, but a 1:1 mixture of Venice turpentine and #7 varnish seems to have solved the problem. I add quite a bit of the modifier in most cases, as lithography usually puts on a very thin film of ink on the paper.
Kae, a Japanese printer had sent me three cartridges of silicone make there and I have found them superior to the Dow Corning I had found best amongst North American products. Maybe this is one the reason for cleaner printing, so I will have to make a plate using old silicone, to test the hypothesis.
How to make the modifier is posted on my university website.