Not 

or not

This is often tied in with "whether" and, more often than not [to discuss later], it is unnecessary.

First up  we look at: 

In this second edition of Wine and Conversation, linguist Adrienne Lehrer explores whether or not wine drinkers (both novices and experts) can in fact ...
source      see my page

This is better:

In this second edition of Wine and Conversation, linguist Adrienne Lehrer explores whether wine drinkers (both novices and experts) can in fact understand wine words in the same way. Her conclusion, based on experimental results, is no.

See also http://semanticcuisine.yolasite.com/semantic-cuisine.php

 

 

To be continued.