[kelnos]

Every non-US thermostat I've seen that works in Celsius is adjustable by half-degrees, so it seems the manufacturers agree with my feeling there...

[chrismorgan]

Living in Australia and India, I have never encountered such a thermostat. But I do vaguely recall encountering a thermostat somewhere at some point that went up by twos in Fahrenheit.

I would guess you would only encounter ½°C steps on units that support both Celsius and Fahrenheit, so that they’re closer to parity. I don’t think any unit that I’ve owned has supported Fahrenheit at all.