all the maneuvers in orbit were practiced on prior missions. apollo 10 came so close to landing that they had intentionally loaded the lem with insufficient fuel in case the astronauts got any ideas. as for the velocities, it's all relative. both vehicles were moving very fast relative to earth, but very slow relative to each other. like two cars matching speed on the highway, except there is no sensation of speed since there is no air and no objects to go whizzing by.
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