  It is shown that a dynamical quantum group arising from a vertex-IRF
transformation has a second realization with untwisted dynamical multiplication
but nontrivial bigrading. Applied to the $\hbox{SL}(2;\mathbb{C})$ dynamical
quantum group, the second realization is naturally described in terms of
Koornwinder's twisted primitive elements. This leads to an intrinsic
explanation why harmonic analysis on the ``classical''
$\hbox{SL}(2;\mathbb{C})$ quantum group with respect to twisted primitive
elements, as initiated by Koornwinder, is the same as harmonic analysis on the
$\hbox{SL}(2;\mathbb{C})$ dynamical quantum group.
