That GRRM will never finish the books is the worst kept secret in the Spec-Fic industry. The ASoIaF project was started as a repudiation of Tolkien. See his infamous "What is Rohan's Tax Policy?" quote. Now he's at a point where the only logical way to finish the book is to give it the old Tolkien Big-Damn-Heroes ending. And because that fat, draft-dodging, hippy fuck can't bring himself to swallow his pride, get on with the business of writing and refute his own premise? Well it looks like he's just going to sit on his ass eating fried chicken and watching football until his fucking heart explodes.
MAN'S HUBRIS!
Also, when Larry Correia wraps up his current trilogy he's going to include a note about how he conceptualized, wrote and finished all three BETWEEN GRRM's last book and his (highly hypothetical) next book.