The thing we all need to remember is that it is about the music not about the (electrical) science. There are so many things that can’t be explained by science. The main one being how we hear improvements in sound quality. Can it really be measured? As has been said before, "maybe we do not have the proper scientific equipment to measure"?
Anyway, Jumia I go with what sounds the best to me. And to me, larger gauge wire running from the breaker box through the power cord, power conditioner and finally to our equipment has always sounded better to me.
Now as has been stated there are also many other factors to be considered in improving sound quality. But starting with the basics you are right on.
ozzy