I enjoyed AFFC, but the problem is that my fave characters (Arya excepted) did not appear in AFFC.
In that I was not alone; most GRRM fans are fans of Jon, Dany, Tyrion and even Bran. So it made a big difference in the novel.
As for his focus...
GRRM spends a lot of time at cons and doing other things. I would get a little snippy about it - except if you read his biographical notes on his site (he put up some new ones 2 months ago) you begin to understand pretty quickly that GRRM's life has ALWAYS revolved around attending SF cons.
In that regard, GRRM is the real deal; he is a genuine *fanboi*. His whole adult life he's been going to them. Moreover, it would seem every love interest in his life - he met at a SF con.
He's been going to them for over 35 years and it is something he and Paris love doing together. A guy who goes to SF cons is very much WHO he is. So...I guess we can't begrudge a man that.
And it's worth remembering that GRRM goes out of his way to be accessible to fans. In fact, I can't recall ANY major author (let alone a genre #1 best-selling author) who is as personally accessible as GRRM is. I think that needs to be taken into account too. Some of these guys you never see. Whereas GRRM organizes a pizza crawl online and tells you where he will be so you can come out with him for the night.
Still - even with his con attendances in past years, he found a way to write.
My guess is that when you really NEED the money those novels generate to pay the rent, it tends to focus your efforts more.
I had thought we would get ADWD for a November 2007 release. While that is still possible - he'll have to get his ass in gear PDQ for that to happen.