I think I see what you mean.
Psy-fi who developed the feature was not ready to make so drastic changes to sculpt mode that Pablo did.
Implementing this, as a stroke method, was allowing its use with all brush deformations without creating a new tool.
But it has disadvantage to force user to reconfigure brushes or create new ones, each time, user wants to apply a sequence of several distinct deformations to a spline.
Old workflow is several stroke methods per brush deformation.
Pablo started to change that.
He brought the idea of several brush deformation modes for certain brush tools.
And he created a Mesh Filter tool where user changes filter deformation mode.
You can use a curve stroke method for mask brush, invert mask and then, use several Mesh Filters.
Original proposal of Pablo contains the idea of brush nodes.
A brush deformation defined by nodes could correspond to a sequence of several current ones.
If Pablo makes that a reality ; just using curve stroke method for a brush with brush nodes would be equivalent or more powerful, than a dedicated curve tool able to switch brush deformation mode.