Angie, I assumed that returning the shirts to the store after wearing would be abusive of the return policy. I'm sure Nordstrom would happily take it back - if you say it's fair game, I'll go for it.
Sarah, I did notice that limitation. I will keep my regular size yellow but I could echange my petite red shirt.
Modgrl, there aren't any bust darts on this one. When I wear the shirt, I am quite conscious of the "butt flap". I remember thinking "if it was just an inch shorter, I would be so much more comfortable" and that is the exact length difference between petite/regular.