We propose a non-humanlike spoken dialogue design, which consists of two elements: non-humanlike turn-taking and non-humanlike acknowledgment. Two experimental studies are reported in this paper. The first study shows that the proposed non-humanlike spoken dialogue design is effective for reducing speech collisions. It also presents pieces of evidence that show quick humanlike turn-taking is less important in spoken dialogue system design. The second study supports a hypothesis found in the first study that user preference on response timing varies depending on interaction patterns. Upon receiving these results, this paper suggests a practical design guideline for spoken dialogue systems.