Had an interesting observation today:
It's well known that you can't bindingly close a question as a duplicate if you were the first one to add the tag you hold the gold badge for. But apparently you can add a tag you hold a gold badge for and then edit the duplicate list (we did this purely for science on a duplicate we wanted to delete anyway):
https://stackoverflow.com/posts/16086086/revisions (10K rep on Stack Overflow required)
This seems like an oversight. Shouldn't the duplicate list perform the same check the dupehammer does in ensuring people who added their gold badge tags can't wield dupehammer power for that question?