Is there an afterlife? Is there free will? You hone in on an eternal question...and I one I have been asking for a year now.
In brief, the only place I have found using charcoal is Old Village of Shoreline. The caveat is that they employ an unusual hybrid system where the coal fire is ignited or perhaps even supplemented by gas. Whatever charcoal they do have imparts some measure of the delectable smokiness, which I agree is essential. However, the meat and banchan quality there is second rate, so much so that I prefer the higher grade food cooked over the dissapointing gas apparatuses at Sorabol or Ka Won in Lynnwood.
With the growing Korean presence here, I remain hopeful that a true charcoal contender will some day emerge.