I'm kicking around making a top quilt. I want a 40*. It seems that some of the cottage mfrs. are doing a sewn through for this temp. rating. It seems that this would cause cold spots vs. making one with baffles, like Adam at HG uses. If making the sewn through design, how would I figure down fill? L x W divided by fill, as in it would just be a tube? Or. would I add the 1.5" per baffle to one layer to get the proper loft, thus one material side would be larger than the other? A little on the confused side. I got it on making one with baffles, but sewn through is confusing me a little.