i don't pre-run hot water in the tap. my dishwasher meant to run pre-wash with "whatever" water (and is quoted in article, having hot water in prewash can actually stain things) and it washes everything perfectly. in fact all dishwashers i ever had washed everything fine (as long as they didn't have physical malfunction).

if dishwasher manufacturer thought that prewash needs hot water, it would have heated it to appropriate temperature like it does when it needs to.