25 October 2018
Design Modeler allows you to modify the original curves that occur before the Blend.
As SpaceClaim has no history, the way to achieve this, as ruggerostark points out (in Italian), is with the Tweak Face tool. Inside there are Edit Method choices, and the one you want is Blend Curves. This reverse-engineers the minimum set of curves required to re-define the selected face, and allows for Control Curve, Move, and Scaling to be done to any selected definition curve. The neat part about it is that it works on faces in general, not just faces that were originally created as Blends. It effectively Edits the selected Face as if it had been blended. This is patented and fairly advanced SpaceClaim functionality, albeit somewhat buried in the UI.