"...There is nowhere in the AFM or QRH that states or gives you information that would allow you to land other than a flap 45 configuration with a perfectly working aircraft or in other words in a "normal ops" situation.
The only time you would land with flaps 30, 20 or 0 would be with a flap failure...."
That's not true for the 605. It's in the Operating Manual....
If in icing conditions with flaps extended, if buffeting can be alleviated by reducing the flap setting, the pilot CAN at his DISCRETION, land at this reduced flap setting.
Refer to the Abnormal procedures - Flap Failure, for distance and speed corrections...