It is useful because it means you can strategically identify a much smaller set of users to focus on. If you get the seed group to trigger, you get massive payoff. And so you can target initial messages to them, and analyse who takes action and who doesn't and why, iterate, and retarget on the seed group rather than wasting lots of time on the much larger full network.
True. I guess I'm just a bit skeptical about whether this would really work. And as others pointed out, if marketers start using this type of targeting, then this "seed" audience will be over-saturated.
