better control of cutout

docs/using/combining.rst

@@ -163,7 +163,7 @@ can be useful to control the behaviour of the algorithm at the edge of
 the cutout area. If no value is provided, the algorithm will compute its
 value as the smallest distance between two grid points in the global
 dataset over the cutout area. If you do not want to use this feature,
-you can set `min_distance_km=0`.
+you can set `min_distance_km=0`, or provide your own value.
 
 The plots below illustrate how the cutout differs if `min_distance_km`
 is not given (top) or if `min_distance_km` is is set to `0` (bottom).