Mostly right, the 1000lbs of tools and supplies stay in the truck 24x7 which is why when I need to move anything of any size I have to hook up a trailer to do so. The light loads I've been towing most weekends are right about 3000lbs and the occasional heavy loads I tow (it's been being about 4-6 weeks between big loads) have been about 7000lbs.
If I were to do an 'off the cuff' average of my own, I'd say I see a max of 23-24MPG with just the truck and it's typical payload, about 17MPG when towing the 3000lbs, and closer to 12MPG tugging on 7000lbs. With a 36 gallon tank and the short trips I generally make (less than one hour of travel), I've always got a good mix of all of my types of driving. When I hand tally the MPG it always figures out to between 18.7 and 19.3 MPG. Dash monitor typically stays at 19.0. I'm pleased with that, my previous truck liked getting 15-16MPH on a daily basis and 7-8 when towing a load.