One of the problems with having an iconic wine among your offerings is that other, equally worthy wines are often overlooked or diminished in the eyes of wine lovers. But such is life. With its latest releases, Australian superstar winery Henschke has moved to align the vintages of several of its top wines, all Shiraz: Wheelwright, Mount Edelstone, Hill of Roses, and the legendary Hill of Grace. Ken Gargett tastes.