  We establish an isomorphism between the 0-degree \"uberhomology and the
double homology of finite simplicial complexes, using a Mayer-Vietoris spectral
sequence argument. We clarify the correspondence between these theories by
providing examples and some consequences; in particular, we show that
\"uberhomology groups detect the standard simplex, and that the double
homology's diagonal is related to the connected domination polynomial.
