"
False comparison. If you bought the cheap welder and opened it up and twiddled it to make it as good as the more expensive one then that is fine and totally lawful. "
The DMCA does not prevent you from doing anything to this welder except trying to work around their firmware to get something you didn't pay for.
You are, in fact, free to take it, twiddle the inside bits, write your own firmware, from scratch, and use the hardware in it.
You just can't take their software and hack it to do it
"The complaint about the DMCA is that it gives a trivial distinction which many users could presumably self-upgrade otherwise the force of law.
"
You have not actually shown this, because of what i said - you are free to upgrade it as you see fit. You just have to not use someone else's IP to do it. You have to use your own.
The DMCA does not prevent you from doing anything to this welder except trying to work around their firmware to get something you didn't pay for.
You are, in fact, free to take it, twiddle the inside bits, write your own firmware, from scratch, and use the hardware in it.
You just can't take their software and hack it to do it
"The complaint about the DMCA is that it gives a trivial distinction which many users could presumably self-upgrade otherwise the force of law. "
You have not actually shown this, because of what i said - you are free to upgrade it as you see fit. You just have to not use someone else's IP to do it. You have to use your own.