You'll notice that the scientific term for our understanding of electricity is "theory". There are understandings that we have in science that are termed, "law"(IE: 1st and 2nd "laws" of Thermodynamics, The "law" of Universal Gravitation) In Science, when something is proven by The Scientific Process(or "method"): First a "hypothesis"(or "theory") is put forth. Then it is proven(or not) by repeated experiments. If the phenomenon can be (1) repeated, (2) observed, and (3) recorded: It is then considered a "Law or Scientific Fact." when testing an hypothesis or a theory, the scientist may have a preference for one outcome or another, and it is important that this preference not bias the results or their interpretation. A most fundamental error is to mistake the hypothesis for an explanation of a phenomenon, without performing experimental tests. Sometimes "common sense" and "logic" tempt us into believing that no test is needed. At any rate: Electrical or Electron Theory is still just that. The theories that have been put forth concerning electron flow can hardly been observed at the Quantum level at this point in time, thus they are not observable. Some experiments have been conducted of course but nothing to date is set in concrete. In fact: The theories are still constantly in a state of "flux." Read this article(from 1962), and then see if you can find something since that "proves" anything about electron flow: (http://www.philsoc.org/1962Spring/1526transcript.html) Note the summation states: "It is possible and in fact likely that some basic new principles and ideas will have to be added to what will be left of standard quantum field theory in order to provide for a complete and consistent description of electromagnetic interaction, and, in particular, of the electron. The future will tell which of these various conjectures are valid. If, nineteen years from now, the fiftieth Joseph Henry Lecturer should again discuss the theory of the electron, the chances are good that he will know the answer to many of these questions." That there are so very many that can indeed HEAR the improvements that various cables, interconnects, etc. make in our systems can be considered "Empirical Evidence", and (without proof that there are Quantum Laws that control those improvements that they make) enjoy the resultant music!