That is a very odd sentiment you are expressing. I love how active he is with his fans, and I doubt it is slowing him down very much. As others have said, he is very prolific. He has multiple projects going at all times, and in terms of word count per week, I don't remember the number off hand (he said it either in a Writing Excuses or during a BYU lecture) but I seem to recall it was over 10K/week, every single week.
Regarding the gritty, I hesitate to draw to strong of a distinction there because it makes it sound like Brandon's stuff is bubble-wrapped and PG. I've read all of ASoIF and no scene still gets me in a mini panic compared to the first bridge run chapter in WoK. That is the darkest most profoundly disturbing scene I've read (in the very best way).
So in other words, I don't think it is a matter of gritty vs non-gritty content, it has to do with what is emphasized and how. GRRM emphasizes the gritty thing itself, Brandon emphasizes the character's experience of the gritty thing. I prefer the latter in general.