Why the Secret Spell Scroll system would have never worked.

Ummm yes I did read it, is that not obvious?

1. If one of them starts liquidating all of his assets, all the others undercut him and each other in an attempt to make the most profit. (as seen by the recent waves of mts stuff) Therefore, it's much better to wait until you have enough of a stock that you can have nearly a monopoly on the market.
2. Removes chance of loss due to rollbacks.
3. Take protection scrolls as an example. For months hackers wouldn't sell them, and only offered "warding services". Why? If even one got out into the market, it could be duped by their competition, resulting in huge losses for them.
Much better to release them when you have several thousand(in the case of protect scrolls, I've seen pictures in which they literally have 48 slot use inventories completely filled with stacks of 100).
This principle would apply to the things such as 20 att earrings and 27 att raccoon masks as well.