To clarify a few things, low stomach acid does reduce the ability of the body to absorb b12 from food or orally. Low methylfolate in the body reduces the ability to retain b12. So somebody with paradoxical folate deficiency of any cause can be flushing b12 through the body into the urine several times faster than if there are no insufficiency symptoms. Somebody taking folic acid a couple of times faster yet on flushing b12. Folinic acid flushes it even faster. NAC and/or glutathione are the champs at pushing b12 out of the body perhaps 10 times faster than if a person is sufficient with methylfolate to the point of no symptoms. I did thousands of injection trials under various folate conditions and this is the description that holds up at all levels. The progression is quite clear as one goes through about 6-8 stages of different rates of excretion in the urine depending upon the operating folate condition. So even though folate is high during methyltrap the operating condition is one of severe deficiency and glutathione sweeps large amounts of b12 from the body very rapidly. Right now Enzymatic Therapy and Country life Methyl B12, that specific product number 6304, are the two MeCbl brands that are most effective. Anabol Naturals Dibencoplex is a 5 start AdoCbl with noticeably more activity than the other brands and without folic acid. When active b12 comes into the system and is high enough, above about 100mcg absorbed, it is available to all tissues on all levels and can wake up nerves that hadn't been noticed fading away, making for all sorts of tingling and such. My experience is that these first ones awakened are the first ones that heal over about 9 months assuming everything else that is needed is in place. Low potassium was first considered as a result of blood formation, but that is an artifact of CyCbl as that was the only thing they considered in those days, effect on blood cell size and one of the only things that CyCbl was actually relatively effective for. So now with MeCbl/AdoCbl effective across the entire range of b12 deficiency symptoms, hundreds of them, more things healing start the need for potassium and maintains it longer.