My point is that the IR OUT appears to only serve to pass data that is provided at the IR IN - thus making it a "pass-through." The IR IN jack would send its data to the same place that data from the IR sensor goes, but it would also connect to the IR OUT to pass that data back on down the line. If that were the case, the IR sensor would lack any connection to the IR OUT (since it is simply a copy of the data from the IR IN jack). That scheme matches all of our first-hand experience.