Pros of dual quaternions

doc/source/user_guide/transformations.rst

@@ -367,8 +367,14 @@ component and the scalar 0, and rotation quaternions have the same ambiguity.
 
 **Pros**
 
-* No singularities.
+* Normalization is a simple operation: scaling the dual quaternion to unit
+  norm. Note that only the orientation part defines the norm of the quaternion,
+  since :math:`\epsilon^2 = 0` (see
+  :func:`~pytransform3d.transformations.check_dual_quaternion`).
+* Easy interpolation with
+  :func:`~pytransform3d.transformations.dual_quaternion_sclerp`.
 * Efficient and compact form for representing transformations [7]_.
+* No singularities.
 
 **Cons**