The grains · Fig. 3
Grains this hour: all counted, the rest refused
Every buy is checked against every flower the bee came from. A pair that fails one condition is refused, and the reason is kept. When in doubt, the grain is refused.
Counts of candidate pairs (bee, A → B) in the demo epoch. Most are bees that did not hold A long enough or enough of it: that is the rule doing its job.