Is normalization process needed?
To answer your question, yes normalization is needed.  

Common sense is a relative term and is open to interpretation.  RDBMS's have been around since the 1970's.  Normalization has been put into use on countless projects over the past 30 years, much to the benefit of the applications being developed.

The most complex time-consuming problems I have worked on in the past 15 years can be directly attributed to the database designer's lack of understanding (or willful ignorance of) the rules of normalization.

If you don't have the time to design a database properly, then you are in the wrong field, or are working on a project that is doomed to failure.