Hi Ryan,
Can pigs clear a lawn? Yes.
Will the grass provide nutrition? Some
Will the pigs need extra food while in that place? yes
Will the pigs make holes all over the place and leave stuff behind? Yes
If you want pigs... that might work ok. If you just want to plant better grass... I feel like there might be some methods that are less work and faster and don't involve pigs.
1. Don't remove the grass at all. Just scalp it as low as your lawn mower will go. Then plant the new seed at the time of the year that that grass grows the best.
2. Rent a sod cutter machine for a couple days, strip the sod off, and pile it to make
compost in the corner... then plant the new grass.
"The future is something which everyone reaches at the rate of sixty minutes an hour, whatever he does, whoever he is." C.S. Lewis
"When the whole world is running towards a cliff, he who is running in the opposite direction appears to have lost his mind." C.S. Lewis