Before revision: Two buses together on the same route In public transport, bus bunching, clumping, convoying, piggybacking or platooning refers to a group of two or more transit vehicles (such as buses or trains) , running along the same route, which were scheduled to be evenly spaced, but instead run in the same place at the same time .
After revision: Two buses together on the same route In public transport, bus bunching, clumping, convoying, piggybacking or platooning is a phenomenon whereby two or more transit vehicles (such as buses or trains) that were scheduled at regular intervals along a common route instead bunch together and form a platoon .