He probably didn't want to get his normal account red tagged because as we all know, it usually happens when you try to attack DT1 or highly trusted members.
This is especially true for those on Blazed's trust list, and you are correct 
Yes, my trust ratings remain, sometimes years after the fact. What I've found is that a lot of the people I've tagged in 2016 ...
Maybe I was not clear (or maybe you did not read very closely). There are instances in which you leave trust for behavior that took place a long time previous to the time you left the Red Tag.