Is it advisable to set body velocities directly, instead of applying a force or torque?
You should only set body velocities directly if you are setting the system to some initial configuration. If you are setting body velocities every time step (for example from motion capture data) then you are probably abusing your physical model, i.e. forcing the system to do what you want rather than letting it happen naturally. The preferred method of setting body velocities during the simulation is to use joint motors. They can set body velocities to a desired value in one time step, provided that the force/torque limit is high enough.
