Hi, I've been making my own juice for a few months now and I've been pretty happy thus far, but of course always looking to tweak and improve. I spend a lot of time on the truly wonderful e-liquid-recipes website and whenever I go into the "Notes" section for a particular flavor there's always a ton of people whose only comment is "preferred single flavor mix: 2%" or something like that.
What exactly does that mean? For example if I go to Ethyl Malthol people are saying that a preferred single flavor mix is 3% or 5% or something like that. Does that mean people are making juices where the only flavor in it is Ethyl Malthol?
When testing flavors, you want to find a good guideline percentage to use that flavoring at. All they mean is "I tested this flavor at X% and found it works best for me there."
Preferred single flavor mix means what you said, that is the only flavoring they used at the average percentage listed.
What is More likely is they are testing out how strong the additive is and ELR just auto generates that info for all the flavors in the system.