You guys are nuts. My tub is about 18' from the house. Just about anything in the single digits F and colder is too cold to get out, close the tub and get inside without freezing your arse off post-soak.
If I had a BAC above .10 perhaps I'd do it. But in a more sober state single digits is COLD.
You have to turn your tub temp up. In the summer we may want to soak for an hour at 101 or 102, but in the winter, or 1F like lat night, we soak for about 20 minutes at 104-106. When your head, face and neck are still above the water line we can enjoy the hotter temps. When I get out its no problem grabbing the robe, and closing up the tub. I have video to prove it, but its not suitable for posting here.
Now wind places a big factor. Last year I was in the tub at 4F no wind and it was great. The next night it was 20F, but a 10mph wind, that was much colder.