I think it's the other way around. Particularly given the concept of thermal mass, some people might not feel that depriving a cooker of electricity for a couple of minutes was a good reason for delaying changing a light switch. In the absence of indicator lights, I doubt that the cook would even notice in most cases.Oh well - I guess I'll just have to remain completely unable to understand why some people think that changing a light switch is such an important thing to do that it must not be allowed to wait until the cooker isn't being used.
Kind Regards, John