I always thought of "manipulative" as having a negative connotation, kind of the ability to get someone to do something s/he will probably regret later which s/he wouldn't normally do without your urging. Essentially controlling others for ulterior motives.
Haven't read through the whole thread, so maybe this was mentioned but my experience is that ENTJ's are "very good" at the bolded part. I wouldn't say it's always something that the person will "regret later" (that's why I didn't bold that part), but convincing people to do something that they wouldn't normally do - yes.
I have an ENTJ friend who will "suggest" that something be done and he'll keep on suggesting it until someone finally does it. And every time, someone ends up doing it. It's almost like he can get anything done that he wants if he just keeps suggesting it. He started a group that has meetings and after a few times of holding the group at the same place, he started saying, "I'd really like to start holding the meetings at other places. Like, a park, a restaurant,
or even your guys' houses. We could alternate having it at each other's houses."
First time he mentioned it, everyone just shrugged - presumably because nobody wanted to do it. Then the next meeting, he said the same thing. Nobody volunteered. Next meeting: "What do you guys think about the idea of opening up our homes to hold this meeting?" Everyone else: "Meh. Yeah, good idea, but...." Nobody volunteered. Next meeting: "So, where would you guys like to have this meeting at next week? Anyone want to volunteer to host?"
And then, out of the stillness in the air (and the uncomfortableness), someone goes, "OK, yeah, I can do it." Several weeks later, the group has every member hosting the group in turn.
With him, he doesn't do it in a "mean way". You don't feel like he's pwning you, but you end up looking back and thinking, "Wait, how did he get me to host this meeting at my place? 4 weeks ago, I told myself that I wasn't going to host at all. Now, he's got me hosting once a month." It's like he just keeps throwing it out there (whatever he wants to happen) until it finally becomes reality. You don't really feel like you got "forced", but afterwards, you kind of do sometimes. And if it is something you regret, then it almost feels like buyer's remorse. You get talked into buying that awesome car or product and when you get home you go, "Why in the world did I agree to that? I didn't even want to do it!" That's kind of how it was for me hosting the group. I didn't feel forced, but later I was like, "What the???"