By Tobias Carroll Some art heists involve careful planning and meticulous execution. Some, like the theft of several paintings from the Gardener Museum in Boston, are still speculated about and remain unsolved. And then there’s the opposite approach — essentially just walking into a gallery, taking whatever strikes your fancy, and making your exit. That might sound way too easy, but it’s basically what happened to a trio of sculptures by acclaimed artist Ai Weiwei that were on display in a Hamburg gallery. An article at ARTnews has more details. The sculptures were made from glass, and in the …