I think the protection needs to be done "off chain" rather than adding a bunch complex stuff that disrupts the on chain behavior.
In my opinion... the type of numerous large thefts that have happened in NXT are unacceptable. It is irresponsible and unfair for us go out and convince people to be a part of BitShares or hold shares or BitUSD in an online wallet if our security policy is "thefts will happen... shrug".
I think this proposal adds a very significant amount of additional security/safety and in the absence of a compelling other plan it is worth additional complexity. I don't think this specific functionality can be done "off chain."
My feeling is that this is well worth implementing and is important.
Security is sooooo important... all this talk about people not voting enough is more related to peoples' fear of losing their stake than anything else.
It is CRITICAL that we can explain to users and shareholders how to safely protect their stake from loss. We need to be able to explain this in a succinct and honest way that does not sugarcoat any risks. We should really have a comprehensive security guide for BTS holders. This is only fair. If we want this to catch on we need to give people the tools to be able to sleep comfortably and hopefully without a huge amount of technical expertise required.