Solve the problem at hand in the way that suits that particular problem best. Don't be a slave to a rigid process. Don't burn out your developers with a dysfunctional system.
Not every problem is well suited to being broken up into single day chunks of work. Not every developer can maintain a healthy relationship to their work with that level of micromanagement. There is a huge amount of anecdotal evidence about this if you read any thread about developer burnout, or modern day scrum and agile. You mention the Agile Manifesto, but seem to forget that one of the primary points is "individuals and interactions over processes and tools".
