Just committed r45110 – “Better smoothing for sculpt cube falloff.”
This is a relatively small change that makes the brush falloff curve work better with clay strips. Clay strips uses a cube-shaped brush; at full strength it looks like the top-left brush stroke in the image. The brush curve can now be used to smooth it without losing the “cubishness” of the stroke.
The first stroke in the second row shows what clay strips now looks like with the default brush curve.