It's Bill's Magic Vapor's 100 drop taste test. It's a method of making a very small representative sample of a new recipe, and tweaking it to your own taste preferences while taking notes on changes you make. Then using those results (including any changed % of flavorings) to adjust your recipe for making a bigger batch. It's found within his blog posts.
That's with only a single flavoring though (like CAP, TFA, etc.), right? Or in the case of OSDIY One Stop Flavors or Blends that are already combinations of flavorings...only 1 of those in the mixes made?
Just Me. But I think it is a Mistake to suggest anything involving Drops to someone who is Very New to DIY.
Don't get me Wrong, I'm not a Drop Hater. Or think that Drops are Inaccurate or Imprecise if the Same Dropper is used. Many of my Recipes are still in Drop Form for Flavorings.
Doing a Range of Flavoring Percentages is Good Practice on Measuring and Mixing Techniques. It also Cost Very Little to do. And if the Mixer is Math oriented, which I believe the OP is, they might not end up Throwing Out Any of the 5 Bottles.
Because once the Total Flavoring(s) has been Established, a Math Oriented Person could probably see how the Other Bottles could be Easily Adjusted.
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And No. I'm not suggesting doing what I posted with Each Individual Flavor. I'm suggesting doing it to the Entire Flavoring if there is More than 1.