Well, it's been working fine for me for about 15 years, let's agree to disagree here. I would still find it easier to remember to change the tires at +1°C than whatever the hell it comes down to in Fahrenheit.
I too live in a region with 80 (Celsius) degree yearly variation (sometimes more; the maximum yearly difference I've lived through is about 90 degrees IIRC: -45 in January to +43 in July), and Fahrenheit makes absolutely no sense to me in this climate.