I love the veggies in the same liquid as the roast (so much flavor from the liquid) - if I have time and the chance to stop home mid-day, I par-boil them the night before and leave them out of the crock pot in the fridge overnight - pop (throw, fling, toss, whatever verb suits) the roast in come morning and add the partially cooked veggies early afternoon and turn the temp from low to high. Works every time!
I like "launch."