I don't think they have gotten worse, I have always been struck by the inconsistent behavior of microwave keypads. I've used plenty, and each time I have to experiment to see if, like you say, hitting the 'add minute' or '+30 seconds' will cause it to start, or require hitting start afterwards. Changing power levels is also a guessing game, do you set time then power, or the other way around? And on and on. I doubt Linux-enabling one could make this worse...