I had my LR4 towed to the shop since it was clear and obvious there was a problem. It would miss, shake the drivers seat, check engine light was on and it would go into reduced power mode. I finally got a callback yesterday.
They said there is an oilier type device (I forget the exact term, CPS solenoids?) that controls the cam actuator that failed which in-turn caused miss-fires. The cam sensor was correct and did its job. It was a waste of money to swap sensors. I wouldn't have agreed to the labor had they asked me for permission since I prefer to run it until there is an easily reproducible problem, but the front-end service guy that did my timing chain work is back now and he is a straight shooter. It seems risky to leave the other functional CPS solenoid and then want reliability for the next 100k so I asked to replace both of them, there is one on each head.