People should still be able to put "trusted" in their thread title as that word is a very relative expression. The thread viewer ultimately has the decision to choose whether the OP is actually trusted. The thread poster can deem himself trusted with 0 vouches because they have known themselves since they were created, while it may take over 9000 legit vouches, plus Omm, mod, and admin. for somebody else to consider them trusted.
Thus I think that the thread creator has the right to put "trusted" in their thread title until a "trusted" user title is created. Even though I never see a thread title that says "trusted" in it and not become instantly wary.
Tl;dr L2read