In this paper, the incorporation of path merging within BT's dynamic speech recognition architecture[1] is discussed. One of the disadvantages of dynamic network generation is the size of the network generated. This is to a large extent due to the creation of many duplicate network portions. The use of a path merging strategy can redress this problem to some extent. This paper discusses the theory behind path merging, demonstrating a 22% speed improvement on a typical recognition task for no loss in top-N accuracy.