My initial thread on the subject was quickly engulfed with a lot of off-topic posts, so I thought I'd post a more comprehensive explanation of what I think may be happening in a Meyer-type WFC. Here I've gone into slightly more detail and put my thoughts in better order.
This then, is the direction in which my research and experiments are headed.
In my opinion, the whole science behind this process and indeed the operation of the WFC relies on the fact that the charge carriers in water are ions and the charge carriers in the rest of the circuit including the electrodes are electrons. The difference in mass is enormous: The relative atomic mass of OH- ion is something like 30,000 times greater than an electron, whilst even the relative atomic mass of a proton (H+) is around 1800 times that of an electron.
In simple terms, what this means is that electrons in the metal can react, and indeed move, much quicker under the influence of a potential difference than can the, relatively speaking, massive ions within the water. And this is the key.
If we can provide a sufficiently short, fast, high voltage pulse across the metal electrodes, the electrons will react and can be building up (or depleting) while the ions are still just thinking about reacting.
Now, the water molecule, being a polar molecule (which is what makes water such a good dielectric) will align to the electric field. Though the water molecules are bigger than both the ions or electrons, in order to align, they only have to make an adjustment to their orientation. Conversely the majority of OH- ions have to battle their way through the water molecules in order to reach the electrode.
So, if we do things very fast, we can have the cathode charged up with electrons and the water molecules all aligned before the majority of ions in the water can reach the electrodes.
Now, the normal Electric Double Layer Capacitor takes a while to form, because this is created by charges on the cathode and the ions at the electrodes in the water, and as long as the charges do not build up too high and so rise above the necessary voltage over-potential (around 1.5 volts) to initiate Faraday electrolysis, this EDLC will remain in tact. Indeed this is the principle behind commercial EDLCs.
Commercial EDLCs are low voltage, very high capacitance, DC capacitors. They employ activated graphite as electrodes because it provides a phenomenal surface area in a very small package, and graphite electrodes with a suitable electrolyte also increases the voltage over-potential to initiate Faraday electrolysis to around 4 volts. If the voltage exceeds this 4 volts, then charges diffuse across the very thin virtual dielectric and current flows.
If we apply a relatively long pulse then the normal EDLC has time to form at the electrodes, and if the voltage over-potential is surpassed then current will flow and usual Faraday electrolysis ensues. But we don't want normal Faraday electrolysis to be the primary process taking place because we know the limitations of Faraday electrolysis in terms of power efficiency. In order to avoid this happening, we have to provide high voltage pulses that are extremely short and sharp.
By applying a very short, very high voltage pulse, the normal EDLC does not have time to form. But, the water molecules do have time to align within the electric field created between the plates as the electrons build up and deplete on the electrodes, and this gives rise to a different kind of Electric Double-Layer Capacitor. Different, because this capacitor is a result of the charges on the electrodes and the polar property of the water molecules aligning to those charges as opposed to charges on the electrodes facing the ions within the water. So at the cathode we have electrons faced by the more +ve hydrogen atoms of the aligned water molecule, and at the anode we have a positively charged electrode faced by the more negative oxygen atoms.
So, if the voltage pulse is of too short a duration the normal EDLC won't have time to form, but more importantly if this short pulse is of a very high voltage, then high energy electrons at the cathode will carry their momentum (the flywheel effect) and they will fly into and react directly with the water molecules to give OH- and H. There will of course be some Faraday electrolysis action after if the normal EDLC has chance to form due to some charges remaining on the electrodes, but the initial high voltage pulse will create gas without current actually flowing through the water.