Not in our case. We’re breaking work into small stories that are self-contained improvements that can (usually) move into production independently of anything else. Typically an individual or team can complete more than one in a two week period. But either way, we won’t break them any smaller than that atomic “completeness” to fit into an arbitrary time interval. The sprint is just for automatic estimating of when we’ll get to a story, how often to demo progress to interested parties, etc.