There's no chance in hell that the TV series doesn't start taking shit from 3/4/5 over the next couple of seasons. I also expect that a lot of the fluff that was present in 4 and 5 (let's be honest, there was a TON of that shit) will be cut right the fuck out. There's no way that the present story lines won't continue until the principle characters die. They couldn't, for example, let Bran's storyline go cold for an entire season, and then pick it back up in season 5, nearly 2 years since we last saw him. That worked fine for Dondarrion, but it wouldn't work for Bran/Arya/Sansa/Tyrion/Jaime or whoever else gets little to no "screentime" in books 4 or 5.