One of the long-standing debates in studies on simultaneous interpreting would pit “contextualists”, who see interpreters’ performances as being conditioned by contextual determinants, against “cognitivists”, who analyze performances in terms of cognitive constraints that would be the same for all professionals, regardless of context. Gile’s Effort Models would seem to be very much in the cognitive camp. However, modeling of the resources used when interpreters make omissions suggests that cognitive management may actively respond to contextual factors such as the aims of the discourse, the strategies of the speakers, and the variable risks of the text items. Analysis of the data from one of Gile’s experiments indicates that the cognitive management of omissions is indeed highly variable. Omissions that are low-risk for the aims of the discourse occur in a constant background mode, almost without sourcetext stimuli, such that in repeat performances they are found with similar frequency but in different places. On the other hand, omissions that incur high levels of risk tend to be repaired in repeat performance. This suggests that simultaneous interpreters strive for non-omission only in the case of high-risk contextualization. Further, since their management skills must incorporate enough contextualization for the necessary risk analysis to take place, the cognitive strategies of interpreters should be modeled in the same terms as those of all other linguistic mediators.