I think it's funny how some people are always so quick to assume that when something is changing, it's because of some evil intent. A lack of curiosity is usually to blame.
You see, GSIs have basically stopped dropping, or are dropping far less than they used to.
If you believe that the number of some or all items in the game is tied to the number of participants, as many do, then you could imagine a situation where one person or a group of persons, over time, could amass a large amount of GSIs, keep them in storage, and create a situation where they dropped only when existing GSIs not in their posession were used up. So, given a certain situation, I guess it is possible that the market could be manipulated.
However, it seems just as likley that something is haywire, or was changed by
MA. I don't know.
As far as the idea of putting things in the TT? I hope one day everything is removed from the TT ('sept for the goldcards) With more player created items, including ammo, toxic shots and tools, we will see a more active economy with more opportunities for players to choose and specialize in different professions.
Of course, this will take a more active and responsive balancing philosophy from
MA in the initial phases... Also, when things are removed from the TT, they should be removed at the same time those items or similar items become craftable. Boxes anyone?