As it is somebody has to interpret No.2 and giving that authority to individual states takes it out of federal purview and recognizes states individual authority. All the nuanced devices of the fed will be removed. Then residents will have much more control of regulation and the voting for or against; if that doesn't work the ultimate vote, as Regan said, we can vote with our feet.
We are witnessing this with the economy, some states refuse to "get it", others are "catching on", and some "never lost it". States regulation will be much more "organic".