tilled dirt becomes dirt if not kept hydrated. I think he means that instead of using water blocks to keep an area tilled and the crops growing you would instead use a sprinkler system. with water barrels and railcraft tanks, this is not only feasible, but a pretty cool idea. With all the new crops from different mods changing the crop growing mechanics could cause some problems. Still, it's a solid idea.
There needs to be a second subforum for the discussion of mod ideas that aren't necessarily requests.