The relative size of the spacing of knots is irrelevant for the NURBS curve. The only thing that matters is that they keep the relation. Note this may not be wise as parametrization may have other uses behind the scenes.
Image 1: 3 differently parametrized knots result in same curve if knot values are relatively the same.
So you can scale and offset knot points as you wish. However you can not make the relative distances between entries different or your curve will change.
Image 2: On the other hand if you change the relative spacing your in trouble. So beware of floating point errors if you need to be really accurate.