Originally Posted by
PedalingWalrus
I disagree that a 4 season tent usually has better ventilation than a 3 season tent. I think that a fundamental design difference of a 4 season tent is primarily to be able to withstand snow load, wind load and be warm. This translates in having heavier poles, more poles, usually being freestanding with full fly coverage or being single wall. Single wall does not usually mean better ventilation.
Condensation is one of the absolute biggest worries one can have when traveling in cold weather. Too much moisture trapped inside the tent means all your stuff is going to be wet, nor can you dry stuff in a tent that's turned into an effective glass house.
Your sleeping system is supposed to keep you warm, not the tent. If there isn't a dry heat source to move air inside the tent and thus move moisture out of the tent all of that water is going to stay inside. In that situation it won't matter whether the tent is warm or not, you'll be cold nevertheless.