This paper studies lexical and structural properties of coreference chains in task-oriented dialogue and investigates their relationship with perceived and factual communicative success. In line with previous literature, our quantitative analysis shows that lexical entrainment is the most reliable predictor of task success, among the ones we compute. But also that there is a complex relationship between these factors -- for example, neither high nor low, but rather intermediate levels of lexical alignment predict high perceived and factual success.