(By Jen Aronoff, jaronoff@charlotteobserver.com) Before opening their stationery store almost exactly a year ago, lifelong paper fans Sasha Harbrecht and Laura Smith spent about two years studying the concept. But all of that research couldn't entirely prepare the owners of Paper Twist, in the Specialty Shops on the Park, on Morrison Boulevard across from SouthPark, for the tumultuous economy that awaited.