Contacts cannot repair an unspecified off-collision limit

This lemma separates two questions. Contacts may normalize a collision extension once the off-collision distribution exists. They cannot manufacture that distribution at a distinct-vertex characteristic configuration.

It also gives a precise obstruction test for a future proof: if a compulsory off-collision normalization were incompatible with every joint prescription on such an open set, then no member of ${\mathfrak{C}}_{\mathrm{part}}$ could repair it. No such universal incompatibility is proved in this manuscript.