In this paper, which addresses smooth spoken interaction between human users and conversational agents, we present an experimental study that evaluates a method for user-adaptive coordination of agent communicative behavior. Our method adapts the pause duration preceding agent utterances and the agent gaze duration to reduce the discomfort perceived by individual users during interaction. The experimental results showed a statistically significant tendency: the duration of the agent pause and the gaze converged during interaction with the method. The method also significantly improved the perceived relevance of the agent communicative behavior.