Suggest a beer on nitro and the mind’s eye will likely turn to a stout or porter. The gas is synonymous with darker, roast-forward styles more than others in the spectrum of beer, and this is for good reason. On the Drink Beer, Think Beer podcast Gary Glass, the head brewer of Left Hand Brewery, Gary Glass of Colorado's Left Hand Brewing explains why Nitro IPA remains an elusive style on shelves and on draught and stout rules the roost.