>While your conclusion is correct, I don't think the explanation is complete. Had she used the term "tall airhead" there would not be an implicit connection between tall people and airheads. The reason the "blond airhead" would be considered offensive is that there is a stereotype about blonds that this expression seems to enforce. There is no stereotypical connection between tall people and airheadedness.

Exactly and that's what makes it so tricky. If you're not aware of a particular stereotype, you can easily put your foot in it.

Tamar