Like everyone else, I try to get the most production out of my stove during this brutal cold. I have one question that I would appreciate others' opinion on. I have a insulated stainless steel liner that is sealed at the top of the chimney. I do not have a block-off plate at the bottom and think I am losing heat up the chimney. Would like to add a block-off plate, but worry it might reduce my draft as the chimney would be cooler. Am I right? The current draft on my chimney is just marginal- would not want to reduce the draft. Appreciate any opinions!