Ah... now I can see. Good points! I will look at this more closely. Already at level 3 her stealth is such that she can walk past just about every baddie and never once get found out...until she goes in for the kill.
You say that shadowwalk goes away the min you attack something, but that is why she would use it to retreat. Jump into shadowwalk and be outta there before anyone would know. If I understand, unlike invisibility, monsters that can detect invisibility cannot detect someone in shadowwalk....right? or No?