The people I'm talking about are very much spineless, without question. They may also be calculating, but if they are they're not successful at it. And if they really understood people they'd realize that a more direct approach would be more successful. I'm not just making up some archtype here; I'm relaying the experiences of myself and dozens of men I've talked to (many who have shared their own experiences with this in other comments).
There are people who are very self-disciplined and calculating, who control their feelings and slowly create experiences that try to control the outcome they desire. That's not the type of personality we're talking about here.