no its fathomable. what if you poison drink a, and she poisons drink b, and you give each other the drinks. so she's going to drink a and you're going to drink b. you both don't know that youre poisoning each other, you only know you're poisoning the other person.
see I've got kind of an expanded definition of Self Delete. If you drive off a cliff 'cause you're too dumb to turn, that's Self Delete. If you walk into a Brazilian favela wearing a Prada suit and gold jewelry, that's Self Delete.
likewise if you're gonna go poisoning someone, you should
at least guess that they'll counter-poison. if you don't, that's Self Delete, man.
whenever I eat food, I offer a little bit to the person next to me so that I can tell whether it's poisoned. that's why I'm not dead via Self Delete.