Pulled Beef - Cider vinegar rub down?

[SoCalBuilder]

I'm gonna take a shot at my first pulled beef this weekend. I bought a tip, something or something roast that looks pretty good and lean (at least from the top). I visited the recipe site and found Mr. Walleye's recipe for pulled beef. My main question was whether or not I needed to do an Olive oil or mustard slather. I'm a big bark fan ;D The rub cupboard is really bare except for a ginormous container of Gunpowder. This seems like the perfect place for the gunpowder, but it is so finally ground, I feel like I am having a hard time getting good distribution if I apply it over a slather.

I noticed in the recipe that it calls for wiping the beef down with cider vinegar and then applying a rub. This sounds ideal to me as it would almost dry the surface and open up the pores a little, letting you really get the rub in.

Any thoughts or suggestions would be appreciated.

Randy