Data useful in analyzing the effectiveness of policies for handling transactions involving client communications is automatically collected at network intermediary devices and delivered to an analysis server as part of feedback communications from the network intermediary devices. The data may be collected according to data collection directives distributed to the network intermediary devices along with updates to policies for handling transactions, those updates being configured to alter actions of the network intermediary devices, for example to accommodate changes in behaviors of content servers from which the network intermediary devices obtain content in connection with the client communications.