... is that removing her from the Pattern would only remove things that Semhirage did directly. It was Rand's physical hands that caused the bruises, not Semhirage's.

The Graendal example illustrates this as well. When Graendal was destroyed by balefire, the thing that she caused directly -- Compulsion on whatshisface -- was undone. But the indirect things were not. If things that Graendal had indirectly caused had been undone as well, then whatshisface would never have come walking back to Rand.