I don't understand how the tablets could be in rinse cycle but powder in wash cycle? They both go to the same container that fully flips open during the wash cycle. Or do you have a device that has some different compartment for powder?
It sounds like a more important step (if you're plumbed into the hot line) is to run your water just before the first cycle so that the machine fills with the hottest water it can get, as not all of them will heat initially.
I don't live in the US. He does talk about some differences. For example, I've never had a dishwasher here that didn't heat it's own water.
I did live briefly in the US and I recall that there were a bunch of subtle differences around appliances. Europe, Australia and New Zealand use the same models and the US gets different models.