It seems as though Zahn is still obsessed with this concept he vaguely outlined thirteen years ago that really was just a cool tidbit of backstory and not worthy of two novels. It was originally used as an excuse to bring Thrawn to the Empire and to serve as part of Jorrus C'boath's backstory, and, of course Lucas hasn't even acknowleged it as canon.
It isn't entirely an uncool idea, but I wish Zahn would move on to post-NJO work, or perhaps Old Republic stories, and not overdo something that has allready had plenty of adequate explanation.
In other words, go ahead and read SQ if you haven't read any of Zahn's other work. If you have, then you allready know enough. I plan to get SQ when it comes out in paperback.