Where are you getting those numbers from? Surely such improvements would be fairly isolated to an acre or two, rather than hundreds of acres. Those numbers (6.8% and 7.6%) aren't in the article.
At an acre or two, you'll be doing most of the work by hand, with using push tools -- rototillers and the like -- for the occasional tough part. These sorts of process improvements are one of those economies of scale things that really only start making sense when you're dealing with an amount of land that you can't just eyeball.