Well, if I put 25$ in my car per week, and it would cost me 26.50$ instead to run the AC and be comfortable, I would use the AC for sure. Not enough difference to be a big deal, even if I care about fuel economy. But if the thing keep turning ON when all you want is heat, then it's very anoying. 6% more is anoying when we don't need the AC and forget to turn it off.
But I am not so bold as to cut a wire and risk voiding my warranty.
View my fuel log 2015 Micra SR automatic: 7.0 L/100 km ... 40.4 mpg (Imp) ... 14.3 km/L ... 33.6 mpg (US) ...