You are DT of your own and allowed to tag anyone if you think they deserved to be tagged.
Yes, of course I can, but the feedback from a member who is not in DT as me will not have much effect 
It will become an unreliable response from the perspective of the other members or even the default trust system His trust still be:
Quote
+0 / =0 / -0
not much effect here, so waiting for DT members to tag is absolutely good compared to my personal efforts.