None of this was forgotten. If they extended their study to a month's worth of -20F, all of that mass will cease looking so attractive. It will work well if all you care about is keeping your house above freezing but most do not consider that livable.
He did? I just scanned through it (watched it fully the first time) and could not find it. Or are you saying he admitted that it was not forgotten and did not read the rest of my post? He sort of admits that in a sideways fashion.