In these cases, it's important to define recovery - in a lot of these cases, brain is dead, and dead is dead. Sometimes, the rest of the brain is plastic enough to "reroute"so you get something back, but most of these cases, to "recover", you'd essentially have to build a new brain...

Keep in mind TDCS isn't a fancy brain machine interface that's intelligently interacting with neurons, it's just dumb direct current that's being sent into tissue...

I think the overall line of research certainly is worthwhile pursuing, just that this specific tDCS project may be being overhyped in just how much it means...