Here's my opinion.  I think he was chopping since Iowa got caught with snow a little ahead of when we would like, I think he wanted to round bale, but probably couldn't with the snow.  Did not want to leave the stalks in the field since it would effect next years crop.  My guess is with the snow it would not ferment unless this weekend heat was enough to start the process.

Something that I always wanted to try is to use a MC rotary scythe or a stalk cutter that windrowed, followed by and inverter or bar rake to try to settle the dirt and stones out of the windrow, then chop.  I would mix it with syrup like spankey posted the other day and pack in pile or bag it.  I know that would ferment.  If a guy only had more time.

There were a few guys around here that used to chop stalks like you are talking, but now I think they have them round baled and tub ground for time savings, and possibly cost saving too.