From what I have seen, the long term fuel trims should stay at/near zero. The short-terms will fluctuate depending on actual load conditions, and should be predictable. The values for both banks should run pretty close the entire time. During deceleration (off the throttle), there is fuel cutoff, so you will see lambda/air-fuel ratio peak (xtreme lean) during these times. WOT is when the lambda/afratio should be at its' lowest (rich). We would be looking for unexplained spikes in either direction, to see if there is actually a problem. Keep the car's BT on during the tests to mimic realworld conditions.