Chazal say that one of the types of incense used in the beis hamikdash was "chelbina". Chelbina smells BAD but together with the good smelling types of incense the Chelbina also smelled good. In the same way when we have a fast there must be sinners fasting as well and then the fast "smells" good to Hashem.
Haman is the same gematria as chelbinah [95]. Haman alone smells BAD but when mixed with Mordechai he smells good. Mordechai is alluded to in the Torah in the name of the pleasant smelling herb "mor dror" [parshas Tetzave] translated by Unkelus as "mira dachya" [sounds like Mordechai].
Maybe that is why we should drink until we don't know the DIFFERENCE between Arur Haman and Baruch Mordechai. We must mix them together and it will smell good.
Chelbinah equals Haman.
[I might have seen this idea somewhere but I don't remember.]