Delete any Boss knowledge at Annolisa Rosie, ONLY, if it is easily acquirable from an NPC shop or conversation, even at the cost of energy, until a conversation or sale proc's S Grade Knowledge. So having an Alt set up at Annolisa rose and another character at the NPC you're trying to get S grade knowledge from. It can take multiple rotations of this method to get it.
(it does take 10 energy per deletion of knowledge)

at least that's what I was trying to get across. Thanks for the Question of clarification!