> Functionally it makes no difference whether you split near the middle or not -- a truly random selection would sometimes end up with a pile of one, and that's totally fine.

Yeah I just mean I would be very conscious of splitting with a single stalk in one group and would wonder if that was really a 'fair' selection or something I did intentionally since I know the exact number of the yarrow in one hand. In practice, I can't imagine anyone would make a selection like that, even though in a truly random system it would happen not infrequently.