Help in V8 for RemoveMultiKnot is misleading. The top level description needs to be amended to include the ability to remove fully-multiple knots. InsertControlPoint | Rhino 3-D modeling
The top level description of the command is (emphasis added)::
The RemoveMultiKnot command removes multiple but not fully-multiple knots from curves and surfaces.
This states RemoveMultiKnot does not remove fully-multiple knots. But in V8 there is a command line option to remove fully-multiple knots:
Command-line options
RemoveFullyMultipleKnots (Yes/No)
Select Yes to also remove kinks from the curve.