With my secondary character Tohelo, I have now done two potion research sessions. In the first session, I tested 176 combinations and found 10 potions. The second session gave me 24 potions from 203 combinations. So, in total I have tested 379 combinations and found 34 potions.

I calculated that I still need to test about 480 combinations and I have the basic research part done (basic research = filled in all the completely unknown combination results). Once that is done, I can start eliminating the close matches.