Tash affect on Charm

[Zallar]

And beyond the statistics, there's common sense. When charm breaks, you need to either Mez or Recharm the mob that is running at you. You always want to have Tash on board so either will land.

When I used to charm solo if Tash wore off, I would get a safe distance and break charm by hiding so I could re-tash and re-charm.