Patrol Base Boldak, Afghanistan – A casual conversation with an infantryman, who’s had a few deployments here and in Iraq, reveals a happy history of heat, cold and general discomfort along the lines of “I lived in my vehicle for seven months.” That is still par for the course — and a form of shared misery preferred by many Marines. But the procurement system has brought some smart comfort to enhance existing structures, such as these insulating tent liners I watched being installed here. They’re made by HDT for the 100, 200 and 300 series shelters and can bring the…