I've been trying differant stuff with B.B.Qing. Just did this one today.
Bought a whole trip tip and trimmed all the excess fat. Threw it into a pot of boiling water along with onion,garlic, black pepper, seasoned salt.
I let it boil for about 2 1/2 to 3 hours.
Started up only one side of my gas grilland set it on low. Placed my smoker box on the flames.
Placed the tri tip on top rack on the opposite side(so its not on the flames)
let the smoke box burn out (I used soaked hickery chips) and refilled the smoke box.
at this time I used Jack Daniels BBQ sauce and when the 2nd box of chips were done pulled the meat off the grill.
It came out perfect. got that nice caramelized sorta crust on the outside, and the meat was tender enough that you didnt need a
Give it a try