As a cyclist I usually had 4 lights on the front, one central main/steady light for illumination and then two bar end lights that showed the edges of my handlebars (visible front and rear) and then either another flashing light either down low at the bottom of my forms or on my helmet. And the similar at the back.
The amount of bus drivers and taxi drivers that chatted to me at the traffic lights and told me that the set up helped them judge my distance was great. I really think it helps people figure where you are and how your bike is moving. Plus if any one of my lights was hidden for a moment, there were 3 more to see. And at worst if one battery went I have more to get me home safely. I ride with lights on at all time.
The amount of bus drivers and taxi drivers that chatted to me at the traffic lights and told me that the set up helped them judge my distance was great. I really think it helps people figure where you are and how your bike is moving. Plus if any one of my lights was hidden for a moment, there were 3 more to see. And at worst if one battery went I have more to get me home safely. I ride with lights on at all time.