The leader mobilizes people toward a vision, in a phrase come with me: stating the goal and the standards while leaving people free to choose their means, giving feedback against the vision; it rests on self-confidence, empathy and being a change catalyst. It fits situations where change calls for a fresh vision or where clear direction is lacking, and works less well with a team of experts more experienced than the leader. It had the most strongly positive effect on climate in the study (flexibility .32, responsibility .21, standards .38, rewards .54, clarity .44, commitment .35).
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.