duals, semi duals, and illusionaries kinda correct each other. in a way you think the other person is kinda fucked up....yet you love and appreciate them. these relationships are on a corrective course.
with activity, you basically don't see anything wrong with them, they really can do no wrong. i def feel this way about any esfj i've been close to. so maybe what she is saying is that because of this, there is more support and loyalty between activity partners, whereas duals tend to see where the other person is flawed.