Within Court Dynamics as a Human Universal (The Five-Person Threshold), the central operating rule Greene identifies is that appearing too aggressive, or trying too hard to get ahead, makes a courtier look "ugly" and "inelegant" — an aesthetic judgment, not a moral one. This turns both the ruler and other courtiers against the over-eager player, so advancement toward power has to be indirect and shrewd rather than blunt.
Greene cites Napoleon's counsel as the tactical solution: put the "Iron Fist inside a velvet glove." The target feels the soft, velvety touch — but the force is still landing underneath it. The softness isn't a substitute for force; it's the delivery mechanism that keeps the force from registering as aggression.
The reason indirection is required is framed as a matter of how the move looks to observers and to the power-holder, not whether it is right or wrong. Bluntness fails because it is socially unappealing, not because it is unethical — which distinguishes this from purely moral arguments against manipulation. Compare Realism Is Not Cynicism (Machiavelli's Distinction) (Machiavelli's related distinction between describing power realistically and endorsing it cynically).
Self-Disqualifying Value Framing (Positive as Negative) and Fantasy as the Currency of Power both describe indirect routes to influence that avoid triggering the resistance an overt push would.