See the textbox where you can enter people you want to trust there? Put a username in each line. If you put anything there, you will no longer trust DefaultTrust.
Hrm, interesting. Is there a way to trust someone, but not trust one of the people they trust specifically?
You're not trusting them, you're trusting
their judgement. If you disagree with their judgement, remove them from your list. If you keep them on your list, you're doing a disservice to all those who trust
your judgment.