Doesn't the T-Pod also aid in urban environments, when clutter from buildings affects the radar's ability to pick up, say, a vehicle? I don't know enough about how a ground radar works to say, so this is just spitballing.
Even at high altitude, a ground radar might pick up many false positives making it difficult to discriminate between targets and also detect vehicles masked by buildings. Hence the use of the t-pod, possibly in conjunction with JHMCS, to id targets in dense cities. This usage case is supported by this paper from the University of Tenessee that discusses designated point drift in the JHMCS.