You need to be careful thinking business models of economy of scale are "the thing" when applied to farming, especially family farming. I can blow holes right thru that crap. How do you think most of today's large operations got started? And what makes you think no one is left to start up new ones when todays die off? I started farming hiring my combining done and worked in town. First year I had my soybeans all hailed out while waiting for my custom guy to show up. That winter I purchased a 4 year old MF410 and got off that custom operator's list. My acres no way justified the 410 purchase, but, my crop harvest done in a timely manner did. Gradually I have grown to where financially I can purchase the 9670, but, in reality I probably could get buy with something much smaller, say a 7720 size, but Deere doesn't offer it. This is where they are missing the boat.
I think the dealers are probably fighting the importation of small combines from Brazil since they can make so darn much money servicing and programing the old ones for the smaller guys. I'd like to know the break down on dealer service income from programming an old combine and charging the customer $6 or $7 grand, plus helping during the season with emergency breakdowns, verses service income doing warranty work on new combines. Besides, if Deere suddenly offered a smaller, economical, bare bones, cylinder combine for a significantly cheaper price then the bullet rotors, think how that would drop the value of used dealer combine trade in inventory. Guys would say "why pay $100k for a worn out 9510 when I can buy a brand new ---- with factory warranty Deere cylinder for
30% more. I think it is the dealers that are holding Deere back on introducing a small bine in the US, along with all the sales of the 9000 seies they are enjoying.
Training and parts don't have a dam thing to do with it.
And there are and will forever be small farms all across the corn belt. Just the bigger ones seem to be crowding out the smaller ones right now, but wait for a down turn and those big highly leverged guys will suddenly become truck drivers and carpenters. And the little family farming guy that does all his own work and maybe holds down a part time job in town will be going to and bidding on the former BTO's iron. I saw it happen in the 80's, and history always repeats itself.
So you keep on studing your economic models of scale and pat yourself on the back thinking you have it figured out. I prefere to go on life experience in production agriculture.