A quality block system is now in place across the network, where users who ask a series of poorly-received questions (or leave a string of inappropriate answers) are temporarily blocked from posting more. This has helped hold back the tide of awful questions coming into Stack Overflow, and I think the site would have completely fallen apart without it.
However, many people are desperate to have their questions answered, particularly if their job depends on it. These people shotgun bad questions, get their account blocked or rate-limited by the system, and then immediately proceed to create a new account and keep posting. The current mechanisms for blocking the creation of these new accounts are not as effective as they should be.
As a result, at least on Stack Overflow moderators have taken to deleting accounts obviously created to evade question blocks using the deletion options intended for trolls. By deleting these accounts as "this user is no longer welcome to participate on this site", the system builds a temporary block on any posts from new accounts at a location. This is extremely effective in stopping users who create account after account to dump terrible questions on the site.
However, we'd also like to have this annotated on the main account to let us know that someone has a history of creating accounts to evade system limits. At present, we have to open up a second tab to manually enter this in for the main account (and we usually forget to do so).
I'd like to streamline this entire process by having a new deletion option added under the user account actions | delete menu item. Entitled "This user is a ban / suspension evasion account of:", when selected this action would bring up a list of all question- or answer-banned accounts at the account's last IP address.
Choosing the main account from this list and confirming the deletion would lead to a deletion of the puppet account, trigger the same location-based penalties as a "no longer welcome" deletion does, and annotate the main account with the details of this deleted account and why it was deleted.
We currently have a similar process for deleting voting sock puppet accounts, and that works extremely well. I believe this would make it easier to deal with question-ban evaders and formalize the ad hoc process we use right now.
