Capsuleers do abide by the rule one body one mind.
Drifters seem to go for hundreds of bodies with one mind. Well, several actually, Apollo, Artemis, Strategos, etc.
Triglavians seem to be the opposite of Drifters, several (trios, dozens, hundreds?) minds in one… clade leader? The Convocation of Triglav Outside the Struggle was it one “person” speaking with at least 3 voices?