Definitely. Nobody's arguing with you over that
Those two posts were not really boasting about burning 12x DVD-RAM discs in general; they were more about the fact that the cross flashed LG GSA-H10A->H10N was finally confirmed to be able to burn 12x DVD-RAM discs at 12x.
Anyway, on the topic itself, I think whoever wants to put out a DVD writer which is capable of 18x DVD+/-R writing has got to get it to write a full disc in under 5min, otherwise it isn't worth bothering about. The current LG DVD writers using P-CAV writing for 16x burns are faster than Plextor's PX-760A at 18x. The fastest full 16x burn on an LG writer (forgot which model exactly)I can recall, was 5:18.
16x DVD-RAM capability is a fine idea, but only if 16x DVD-RAM discs are made easily available! No consumers outside of Japan can get hold of 12x DVD-RAM discs at the moment.