yeah, Theymos, would you mind telling us the reason Tradefortress was on the default trust list? My speculation was that he had "disclosed security flaws in a responsible manner" as your feedback for him said, but was that the reason or was there another reason?
No. The damage someone in DefaultTrust can do is very limited, so a lot of trust isn't required. I've actually long been suspicious of TradeFortress because he was holding too much BTC, CoinLenders looked like a HYIP, and I've heard some suspicious rumors about him. But I thought that he was very unlikely to go totally crazy with trust. (And he didn't.)
He was on DefaultTrust because his trust list was good. There were only a few problems that ever resulted from his list, but he brought many good people into the trust network. He also seemed to understand the trust system more than anyone else, and he paid the most attention to trust activity across the trust system.
Someone in DefaultTrust is like a moderator responsible for cultivating a good trust network. They need to make sure that anyone trusting them sees many accurate ratings and no inaccurate ratings. Actual trustworthiness is important, but I can quickly respond to any abuses, so it isn't the most important factor in my decision to add someone to DefaultTrust.
The default trust network needs to work in this (somewhat counter-intuitive) centralized way, but you don't need to use the trust system in this way. You can use it more like a web of trust, adding only people who you trust to your trust list.