By law or in theory, riding on the street, whether in a bike lane or not, a cyclist has the same rights and must obey the same laws as a motorist. When you ride on a sidewalk, the cyclist has only the rights of a pedestrian. When riding on a sidewalk, when entering a street intersection, law requires that you dismount and cross the street as a pedestrian, a terrible inconvenience especially if you are commuting. In some cities riding on a sidewalk is illegal. Where there are people waiting for busses they usually block the sidewalk. Motorists coming from a side street or driveway will usually block the crossing. My experience is that streets have a personality. Motorists tend to follow a pattern in speed and behavior in certain areas and intersections. As a result, some streets are best to avoid completely during high traffic times. If a sidewalk or path is completely off-road and made for cycling, use it. However, non-cyclists will use these paths too and, as are many people, oblivious to what is happening around them and put themselves in danger and you as well. Pedestrians walking dogs, children, areas around schools, should be avoided.