Complex sentence: The ability to age is one of much discussion and differing opinion in the wine world with some experts like Master of Wine Mary Ewing-Mulligan believing that Condrieu is best consumed within three years of harvest.
Split into simpler sentences: The ability to age is much discussed and the subject of differing opinion in the wine world. Some experts like Master of Wine Mary Ewing-Mulligan believe that Condrieu is best consumed within three years of harvest.