I'm in the same boat and asked the same question, so far you are getting the same answers (not helpful). I hope you do get some better answers. Nobody is looking for secret recipes just some guidance or a direction to start. Good luck!!
man I am more than happy to help provide a useful answer, but I'm not real sure what you want folks to say??
if you and the original poster believe that saucing a brisket is the answer then honestly that is what you should do.
my honest god answer is that I do very very lightly sauce my brisket slices.....you would barely even be able to tell it was done.
I do my burnt ends a little heavier, but never to the point it's like rib candy.
in all cases, i cut the sauce with something, either water, beef broth, or the natural au jus I have collected from the cook. I honestly can't tell you how I mix it......I just start taking some sauce and start blending it until I get a flavor that tastes good that day and then I apply it to the meat.
I dont put the slices back into the smoker, cause the sauce is so light there isn't a need to "set the sauce". About half the time, I will place burnt ends back in to let the sauce caramelize a bit, but even then it's a spur of the moment thing for me.....because if my burnt ends turn out like butter, I do very little to them and let them stand mostly on their own.
I do this process with various sauces......depending on what is tasting good to me at the time. but it's mostly commercial sauces.
now all of this info and $4 will get you a decent cup of coffee somewhere......in other words, what the hell do I know? I'm no championship cook. I cook 1-4 contests per year. I've done around 15 contests in the last 6 years or so. I've gotten roughly 4-5 calls in brisket and most recently last season got a 3rd place call in brisket at a sanctioned KCBS contest. So i dont make dog food, but there are lots of folks who know a hell of lot more about it than I do. but I hope my answers have helped a bit.