Isn’t it the exact opposite? It you talk to people about something being “twice as warm” or “half as warm” people will assume you are talking about a scale in celcius or something closely related? Because it doesn’t make sense to say “the bedroom is freezing it’s 3/100th colder than the living room!” And no one saying “the bedroom is half as warm as the living room” will be interpreted to be saying that it’s -127 degrees celcius.