This is what as the triad of thesis, antithesis and synthesis. A lot of progress works this way. [http://en.wikipedia.org/wiki/Thesis,_antithesis,_synthesis]

Thesis (established view): SQL/ACID solves all you data problems

Antithesis: Nobody needs SQL/ACID, let's throw it all out

Synthesis: By carefully considering data integrity constraints we can find a more optimal data management solution for a particular problem (alternatively: let's go to the pub!)