It makes no sense to put RL on the right leg. It is a ground wire, we could put it on the pt's forehead and get the same trace. The LL/RL convention only creates more potential for error, because even though RL location doesn't matter, LL does. Switching them and putting LL on the right leg would affect the electrical axis. I say put them both on the left leg, right next to each other. One less thing to screw up. That's my random idea for the day.