1. An apparatus comprising: an implantable cardiac function management device including a programmable controller, the programmable controller configured to include a user-specifiable therapy control parameter set, wherein the therapy control parameter set is configured to include at least one of a rate response parameter, a tachy detection parameter, and a tachy therapy parameter, and wherein the therapy control parameter set is user-configurable to automatically switch from a first parameter value to a second parameter value at a time that occurs between separate user programming sessions of the device; and a remote external interface for the implantable cardiac function management device, configured to be communicatively coupled to the implantable cardiac function management device via a network to a local external interface and via telemetry between the local external interface and the implantable cardiac function management device, the remote external interface comprising: a communication circuit, configured to communicate with the implantable cardiac function management device; and a processor circuit, configured to perform an analysis of physiologic data received from the implantable cardiac function management device in response to operation of the implantable cardiac function management device using a plurality of the therapy control parameter sets, the processor circuit configured to select a particular therapy control parameter set using the analysis.