Inspired by the image below, I'm wondering if multiple accounts are frowned upon on SE. Maybe safeguards are in place at the IP level to prevent abuse.
Possibly, I'm missing something in assuming user3663 knows Driver 8's whereabouts.
Multiple accounts are not explicitly disallowed however there are some caveats. In summary:
Stack Exchange doesn't make accommodations for them - this means that they may make changes to logins or other system functions that may break or hinder their use without notice.
Additional accounts must not be used to do something that you could not do with a single account. This includes but is not limited to:
Using multiple accounts in this way is grounds for warning and suspension. Moderators and Stack Exchange staff can and do take action when multiple accounts are used to artificially inflate reputation or target a particular user.
If you suspect abusive use of multiple accounts, please flag one of their posts with the other reason and detail your grounds for suspicion.
However, having said all that, I believe this is a much more benign situation - the author of that post is unregistered, whereas the person who has suggested the edit is registered. Unregistered accounts only last as long as the cookie does, so users sometimes inadvertently create multiple accounts. In these cases, users can use the contact link at the bottom of every page to merge the accounts.