Well, I read Gaiman's article, and if that's the approach an author wants to take, then so be it.
At the end, Gaiman states, "...the simple and unanswerable truth: George R. R. Martin is not working for you."
If Martin is not working for the reader, who IS he working for? Who pays his salary, and more to the point, who pays his royalties? In the end, it IS the reader. Without us spending our money on his books, there is no publishing deal and no royalties.
If I go with Gaiman's line of reasoning, then my response is this. Fine, go ahead, write your stories. I'll only purchase them when you finish the entire series, and not a second before that. What motivation could I possibly have to read half of a series and not get to the ending? It just tells me that Gaiman and Martin take their readers for granted.
If more readers decide to take this approach, then here's a clue BOOK ONE WILL NEVER SELL! It's not hard to figure this out. If book one does not sell, the publisher is not going publish book two.
Therefore, while it is debatable that Martin does not work for us, the reader is buying the book(s) in an unfinished series in good faith that the series WILL in fact be finished. One could go further and expect some communication should there be an inordinate delay.
At least I know where Martin (and Gaiman) stand here. I will not purchase any more of the Song of Ice and Fire books until the series is complete. It just sounds to me like Martin got enough money, and he doesn't feel like finishing it. If that's not the case, here's a clue, let your readers know!