To clarify, the new consensus changes makes it almost impossible for anyone to take over consensus without a shed load of stake. The issue here is that the top no. 1 witness also becomes the failsafe recovery account if users don’t have one. @saboin is most trusted and experienced to handle this.
Due to the poor conduct on ferv’s part witnesses are banding together to reinstate saboin. We are planning a feature for the next HF to have this set as a witness parameter so witnesses set who will have this responsibility rather than hardcoded to no. 1 who might not be qualified or want that task.
It’s quite good this is all happening as it serves to stress test the gameable limita of Blurt and so far we are holding up well and innovating to suit as mentioned above.
How many times has this been used on Steem/Hive/Blurt?
I don't imagine many times but it is important to cover edge cases, a black swan event of mass accounts being compromised would make this feature important. Especially in the case of the free account issuer also being the recovery account, if the issuer locks the user out later with password change and are also the recovery account, the user has no chance of getting their account back.