I thought you were referring to an impossible "bearer coin" type of design where PoW wasn't needed when you wrote that 'if only you can mine your own transactions'. Now I understand you meant something else
Yes, something else - I was referring to a POW system with one transaction per block, minable only by the sender of the transaction. I guess Iota is an example of such a system, but it doesn't have to be the only one.
You forget I pointed out to smooth (in our discussion about Proof-of-Stake versus Proof-of-Work in my vaporcoin's thread last month) that assumption fails when the government + oligarchy is the one taking control, because they can charge the cost to the collective.
I guess this is the plain 51% attack? Again, I'd love to hear the key details to any system which claims to address this, which doesn't create much bigger problems than it solves.