When people claim that you cannot follow Islam without hadith, they always forget the one man who did exactly this: Abu Hanifa. Today, the largest school in the Muslim world, the Hanafi school, keeps the name of its founder, but no longer follows his methodology. It has become 'hadithified' to the extent that modern Hanafi followers often use the methods of the people of hadith (hadith-first) instead of Abu Hanifa's methods.