Security is required
No, what you call "security" is a subjective appreciation of the hashrate, compared to a perceived "necessary minimal hashrate" that is by no means "required".
The possible gap between perceived and real need doesn't contradict what I said.
Can anyone walk me through a scenario which results in a responsive & secure network?
Sure :
- the switch to tx-fees-only happens
- nothing extremely special happens
- the market adapts, eventually
- the network is responsive and secure
The end.
No. Without massive protocol changes, the market does not have the tools to adapt to this situation. There have been lengthy discussions about this.
I (honestly) don't understand how the transition from mining-for-bitcoins to mining-for-tx_fees will play out. Sorta' filed it away under "not the time to think about it, will cross that bridge when we get to it." Can anyone walk me through a scenario which results in a responsive & secure network?
Nobody knows exactly how this will happen. But one possibility is that a limit will be placed on the total value that can be transacted per block, and if the resulting network hashrate is perceived to be too low, the limit will be tightened.