Traffic lights control busy junctions. They alleviate traffic flow by changing priorities in sequence, enabling vehicles from one direction to stream easily while cars from another instructions are kept fixed. When driving to a junction managed by traffic control ask yourself exactly what a thumbs-up really implies. Most people will answer rapidly with the reply a green light suggests 'go'. However a thumbs-up suggests more than that, it in fact suggests 'go however only if the roadway is clear and it is safe to do so'.
On your technique to a set of traffic signal if you see a thumbs-up... [...]