I think there's a difference between "being manipulative" sexually and "playing" sexually. I would say that the difference would be in intent. If your intent is to give or share pleasure or arousal then how can it be wrong unless one believes that the pursuit of pleasure itself is wrong due to prudish conformity to "adult" standards of proper behavior (everything from old-school feminism to fundamentalist religious beliefs to the Puritan/Corporate work ethic might apply.)
Also, I think that the core of the advice being offered here is simply that if a woman wishes to assertively initiate sex, she should put the focus on her own body and sexuality rather than the man's body or sexuality. The reason this can be difficult to do is that our culture doesn't exactly promote "feel great about your body and your sexuality" conditions for women. Of course, the greater the anxiety a man needs to overcome to be sexual, the more self-confident a woman needs to be. A perfect example of how this kind of thing can work or not work was that for a while the "trick" of fondling my own breasts in front of my 2bx worked to turn him on. When it stopped working what he said was "I can tell that you are doing it for me not for yourself." He could tell that I desired his reaction not the action itself so he felt pressured to react. Well, I guess sometimes you're peeling an apple and sometimes you're peeling an onion and sometimes you don't know which one until you're left with a handful of nothing.
"Tell me, what is it you plan to do with your one wild and precious life?" - Mary Oliver
