I have a question: Since your raising up your planting area anyway couldn't one just add a good pile of dirt/compost over the sod and plant into it? Mulch around the plant to hold back new growth while the little guy gets established. This way the ground and organisms are not disturbed, and the old covered sod will decompose and give back it's store of nutrients.....
Kind of a Ruth Stout variation of don't like it, don't disturb just cover and go!
Cover and go works with certain types of plants, but it could create a nightmare of regrowth later with other plants. The method Paul describes sounds reasonable to me. Would depend on how deep the top soil under the sod is. Worms often love the root layer of sod and the like, but the filling in of a relatively shallow trench with sod doesn't seem like it would compact enough to kill them in huge numbers.
this llama doesn't want your drama, he just wants this tiny ad for his mama
permaculture thorns, A Book About Trying to Build Permaculture Community - draft eBook