Jail breaking officially granted DMCA exemption ...
so when you say " that part of DCMA has never and likely never will be tested" what you really mean is no DCMA lawyer in their right mind (is there such a thing?) would allow this to be tested in court as the existing Jail breaking exemption already exists (Jail breaking officially granted DMCA exemption | Phones | iOS ...) and so they automatic loose under existing common law rules.
"The violation is that he PUBLISHED the results of what he did with his hardware and INCITED other to do likewise."
NO , that is your perception of the case put forward, it wrong as you conveniently Omit the vital parts required to reach never mind prove such a legal conclusion.
"This is what DCMA prohibits because it defrauds the COPYRIGHT holders of the software sold for the device."
NO, again this is your personal perception, its wrong, it does not defraud, deprive or other wise the copyright holder of anything, the copyright holder has already been payed for the use of their copyright IF the Owner of the hardware wishes to use that copyright software.
if the user and owner of the hardware device wishes to use another vendors software under another licence then they are free to do so.
that users choice has nothing to to with the original copyright holder as if you want to try and tie software copyright to a peace of hardware as Sony did the moment they sold and advertised that device with Linux OS capability's then it's legally clear that part of the so called use of the original copyright has already been payed for by said user to use as required and as they see fit to re-instate that prior advertised functionality.
as you say "You don't have to like it, but you do have to understand it" but you also need to put it in legal perspective not your personal perspective unless you can also show existing case law ?to back up your perception.
and remember you cant cop out by using the mantra but the device consumer contract says this so it is so, Its Not so if that consumer contract is one sided and does not also allow the other party (the end user that buys the hardware) to also enforce their rights, its 'an invalid clause' not legally enforceable on a court of law.