The application of extensional strain to a polymer ultimately leads to random covalent backbone scission in the chain segment with the highest mechanical force concentration. The selectivity of this process can be increased by the incorporation of mechanochemically reactive predetermined breaking points, so-called mechanophores, as well as by the choice of polymer architecture. The conception of mechanophores has led to exciting applications, for example in force sensing and force-activated chemical reactivity. Fundamentally, a mechanophore must have a smaller ultimate strength than the macromolecular backbone in the material under investigation. Engineering of its mechanochemical reactivity is hence necessary, but not straightforward, since intuitive molecular design guidelines for mechanochemistry are underdeveloped. Since mechanochemical reactions are force-biased thermal reactions, the mechanochemical and thermal reactivity are generally interconnected. Several examples have been reported where the mechanochemical reaction has been shown to proceed through an alternative, pseudopericyclic, and Woodward-Hoffmann-forbidden pathway and leads to reactivities or product distributions that are unobtainable by the concurrent thermal reaction. Yet, for nonpericyclic mechanochemical reactions the dilemma remains where mechanophores are conceived by making them thermally labile. This hampers their successful application due to an accordingly restrictive processing parameter space. In a notable example, Otsuka and coworkers have reported the thermal stabilization under retention of the mechanophore character. However, a concomitant increase of scission rate and thermal stability at the same time has never been achieved.