If it only applies to enemies under the effects of Dark Magic, and the only lasting Dark Magic effects are all control abilities, what's the point of this? It doesn't apply to anything particularly threatening (basically all trash mobs in solo play die swiftly to Lightning Form for defense+Overload heavy attack melting them down fast), since so many elites are totally immune to control.
Should I just skip this then, since there's no way to ever apply it to major enemies (e.g. bosses)? It's kind of a disappointment, since 15% crit chance is a lot.