You cannot write a story about winegrower Jean-Luc Jamet without spending a few words on the final split in 2013 with his brother Jean-Paul Jamet. Until that year, they had successfully run the old family domain in Le Vallin, Ampuis, for 25 years, but the differences of opinion ran so high that an abrupt break was necessary. The real cause remains guesswork, that's how correct they are…