Planting open pollinated seed, American farmers were averaging about 25 bushels of corn per acre at the end of the Civil War; by the Second World War, that yield had increased to about 40 bushels per acre. By the 1950's, virtually all field corn planted in the US was either single or double cross hybrid. In the ensuing years, the average yield has increased to almost 160 bushels of corn per acre. Not only are yields dramatically greater, but inputs for fertilizer, herbicides and pesticide are dramatically lower.
Monsanto, by the way, couldn't care less whether you saved and replanted the next generation of their seed corn. Hybrid seeds don't reproduce to type.
Golly, then I guess we are about to see a share holders lawsuit where the share holders of Monsanto sue management for misfeasance for wasting so much company money threatening and engaging in litigation.
/sarcasm
My point wasn't that Monsanto was hurt by seed saving, my point was that Monsanto is using the courts to destroy seed savers.