I did a brisket this past weekend for the superbowl with just splits and a dry pan. After it got up to about 275 and stable, I put in one split about every hour and put a split on the other side of the basket just to heat up the next burning split. I was able to hold 275 easily without it getting too hot, but I could have taken it up higher with more air. I just wanted a minimum "fire" without smoldering. It worked well. I alternated oak and pecan on the splits until the internal temp on the brisket was about 160. I then wrapped, put lump in the basket, filled it up with water and let her go until probe tender while I napped. Worked great!
My vault settles in right at 250-275 and will not go higher without a really roaring fire with water in the pan. I can get it higher but the whole basket better be going to get above 275 with a pan full of water.
LBGE, Traeger 075, Pitmaker Vault on LT-1 Trailer