I had never heard the turn tea sipper until I met my husband - a grad of U of H. And I lived in Dallas for 3 years before moving to Houston & I went to OU (& grew up in Norman, that has a big rivalry with UT. So I have never understood the term myself. Maybe it is something the Aggies started long ago when it was an all cadet school. Being a retired librarian, I should research it, but no time for now.