If you are using only footpads, then that can be a real problem. The current travels up one leg, across, and back down the other. It does not reach the upper torso. For true reach, a 4 point contact is needed. If you are doing positive offset, then 3 points should be positive and 1 negative. For a bi-directional setup where the outputs alternate, like the BBBE, then you should use a balanced 4 point contact, 2 positive and 2 negative.