RFC email pattern is very complicated (see http://ex-parrot.com/~pdw/Mail-RFC822-Address.html and http://stackoverflow.com/questions/201323/using-a-regular-expression-to-validate-an-email-address). I run above "pragmatic version" on database of 4187 real addresses. Only one failed and it was typo mistake. 

However, I agree, that we could aim for something more complex. Any pattern suggestions?