That odd time-lag between downloading a track way ahead of its US release and then its second coming as a real actual single over here. Witness “Milkshake”, “Get Low” and now “1 Thing”, it’s worked in Amerie’s case though as the song has coalesced from an intriguing misfit into an all-conquering radio hit, its buzz of digital potential fleshed out as a real-world pop event. A fancy way of saying it’s been a “grower”, then.