First time putting anything on my blacklist.
I tried blacklisting posts with less than 10 score but exclude the ones posted within 7 days. My attempt was "score:<10 -date:week", but that seemed to block ALL posts that have less than 10 score, disregarding the exception.
I read the Blacklist Help page, and my formula seems to comply with the standards.
What's wrong about it?

It doesn't look like the blacklist supports the date metatag at all, which is quite unfortunate.

I guess nobody has wanted to go out of their way to implement the strange date syntax it uses in JavaScript.