From the help (LV851):
QUOTE
Can someone elaborate a bit more on this? I mean what if I'm not using dynamic dispatch. How does the Mark As Modifier help or hinder me with standard code? I don't really get the point of this option.
I'm fairly confident when I say this: If you're not using dynamic dispatching, turning on this option can only hurt your performance.
There may be some corner case use for it, but I'm not aware of one. All it does is force LV to treat something that wouldn't be a writer to be a writer.