The moldboard plow IMO is the best way to grow corn on corn if you have the right ground to handle it.

Problem: you need alot of time, alot of horsepower, and an extremely good operator to plow!  We are not going to plow much any more because of this (except for the good operator part)

Not to mention with a chopping cornhead you can do a pretty good job of tillage if you mow the stalks to the ground.

Both of these pictures were taken a few hours behind the combine.

We have found that we can get just as much of a yield bump by a good job of tillage (not by plowing) and splitting up our N via. siddressing.