I have a very similar story. DVLA have now had the information they need from my consultant for over 20 weeks and they keep saying my "case is waiting to be seen by our medical advisors, the reason for the delay is due to the high volumes of work within our medical section."
They also say my GP can certify me fit to drive, but she's reluctant to do so as she hasn't received any detail on my case from the consultant. I've contacted the consultant to ask him to send the information on, but no joy so far.
I've also enlisted the help of my MP, but no progress to report so far.
My SAH was WFNS 1 and was treated by coiling in July 2013.