Admittedly, I'm not an expert in tdcs. My experience is limited to what might be considered the typical, prevailing, suite of neuro-electrophysiology methods: s

Admittedly, I'm not an expert in tdcs. My experience is limited to what might be considered the typical, prevailing, suite of neuro-electrophysiology methods: stimulating electrodes + glass pipettes into acutely sliced rodent hippocampus/cortex; same for organotypic slice cultures; in vivo implantation of multiunit recording electrodes + fiberoptics into rat cortex. I think these methods provide enough background in ephys to formulate an educated opinion on tdcs. Also note that I'm just as cynical, if not more, when it comes to research reports using those established methods I mentioned above. Suffice to say, it's not the methods that concern me, it's reports of some marvelous thing that happened while using such methods. You are right though, the claims about the utility of these commercial devices (and really any non-implanted device) that are by far the most dubious.