its simple, replace the current DT-1 members with the DT-2 members.. then allow the system to do what it is supposed to do, just because the people you set 4 years ago were the right people for the job then doesn't mean they are the right guys to fight the scammers now.
Which boils down to the same point again : Why would I trust some random people as part of my Default-Trust-List ? I'm afraid that you aren't getting the point conveyed by theymos.Goal is to alter the 'centralised ' nature of the trust network regardless of iteration they follow in the list..
compare the number of DT-1 members and the number of DT-2 Members.. its the simplest way to re-jig a dated system that needs a change to fight the spam, farming & scams. Who better to be part of the new system than the guys that are actually tagging people now.