Why should you De-normalize?
While normalization makes it easy to input correct data , it also makes it difficult to get it out. This is why you should de-normalization your data. The advantages of de-normalization are faster selects & reduced joins at the cost of slower updates and additional storage.
Personally I have seen up to 300% performance improvement with de-normalization when complex joins are involved. I fully support exploring of de-normalization to dba’s/developers.