Feedback from field deployments of machine translation (MT) is instructive but hard to obtain, especially in the case of soldiers deployed in mobile and stressful environments. We first consider the process of acquiring feedback: the difficulty of getting and interpreting it, the kinds of information that have been used in place of or as predictors of direct feedback, and the validity and completeness of that information. We then look at how to better forecast the utility of MT in deployments so that feedback from the field is focused on aspects that can be fixed or enhanced rather than on overall failure or viability of the technology. We draw examples from document and speech translation.