I have again to take issue over the general question of reverser effectiveness. It seems that the 320 requires an increase of only 55m in LDR for all runway conditions according to the TAM MEL. I must therefore assume that the 320 reversers are almost ineffective. The Boeing 737-700 requires an additional 370m for braking action 'Poor' with 1 u/s and 970m for both, which is far from 'little effect'.