Gents - the weights entered into the INIT B page of the FMS were correct. The problem was with the laptop and the speeds are then loaded into the PERF page..
Which is why we compare the "green dot" speeds (minimum clean) calculated by the laptop and the FMC on the PERF Page. If they match, laptop and FMC have the same weights. To enter the right weight into the FMC, but 2XX tons instead of 3XX tons into the laptop is by far the most common error. This is recognized by comparing green dot speeds.
Cheers,
DL