The debate on whether to heat/not heat coop is based on how many birds you have and what breed of bird. If you have several birds in a coop,they probably will be fine,but if you have a small flock of bantams(mine are silkies)they may require heat. To all against heating coops,you probably have several birds and do not experience the cold and wind chills i have in Manitoba. I can guarantee my birds would be dead if my coop was not heated.
Yes,wind chill does matter,anyone that thinks differently probably has not experienced a -45 wind chill. I come from a family of plumbers(father,husband,brothers)so i know what a sever wind chill does to pipes. I have a heated crawlspace under house,my cats love to dig under the snow/skirting/insulation to get into crawlspace(it is all sand and heated)if temp are -39 C no problem with the small opening they have created,but if it is -40 or colder with WIND CHILL,pipes freeze and/or pump. Last night we had to thaw out a piece on our pump that had frozen due to wind chill. If my coop was not heated,not only would i have been dealing with frozen pipes,but frozen dead birds as well. The point is to all that repeatedly claim wind chill is not a factor,think again,it can be deadly to any animal this is a fact.
So stop with the repeated saying that heating a coop is not necessary and harm will come to your birds if you do. Some birds will die without heat. Just b/c it is not how you do things,does not make it wrong.