I just spent half an hour playing and you are right, the manual is wrong. But the description in the xml isn’t quite right either.
Here is what I found:
Parameter 1: Ramp Rate Z-Wave - Controls how fast the light turns on or off from a ZWave command
Parameter 2: Dimming Speed Switch - controls how fast the light changes when the switch is held down
Parameter 3: Dimming Speed Z-Wave - controls how fast the light changes when Z-Wave tells it to go from 1 level to another (Ex. 20% to 80%)
Parameter
Parameter 4: Ramp Rate Switch - Controls how fast the light turns on or off from a switch press (not hold)
My confusion was caused by having parameters 3 and 4 set to 101 then changing parameter 1.